
BAUSCH &L9MB 
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iTOGRAPHIC OBJECTIVES 


SHUTTERS AND ACCESSORIES 


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PHOTOGRAPHIC 

4* LENSES 4 * 

Shutters and Accessories 


“THE BEST OF EVERYTHING OPTICAL” 



BAUSCH & LOMB OPTICAL CO. 

n 

ROCHESTER, N. Y. 


MAIN OFFICE AND MANUFACTORY, 515-545 N. ST. PAUL ST. 


Chicago Office: New York Office: 

Stewart Bldg., State and Washington Sts. Townsend Bldg,, Broadway and 25TH Street, 

CHICAGO. NEW YORK. 

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13160 


Copyrighted 1S98 

Bausch & Lomb Optical Company 

Rochester, N. Y. 


THE GENESEE PRESS. 

THE POST EXPRESS PRINTING CO., ROCHESTER, N. Y. 




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A FEW WORDS ON 
LENS MAKING 



L ENS making has been our specialty for nearly half a century, and v 
^ embraces every conceivable form of lens, from that marvel of accur¬ 
acy, the object lens of a high-power microscope objective, scarcely 
half the size of a pin’s head, to the huge 36-inch lenses which serve as 
reflectors for the searchlights of modern men-o’-war. 

The development of our business, from its most insignificant beginning 
until we are, at the present moment, the largest manufacturers of lenses in 
the world, has been due solely to the painstaking, accurate, and conscientious 
work which has been bestowed upon each individual one of our products, 
coupled with a never-tiring vigilance in securing for our works the most 
improved mechanical 
equipment, the best raw 
materials, and every ad¬ 
vance which science has 
made ' in constructive 
formulae. 

How many users of a 
lens realize the number 
of skilled hands and the 
number of operations 
through which the various 
parts have passed on the 
way from the rough ma¬ 
terial to the perfected 
objective ? A Village of Com P licated Devices. 

So exacting are the requirements of modern construction, that the 
processes involved are multiplied until a good sized village is employed. In 
our manufactory nearly one thousand operatives are actually employed in 


Bausch & Lomb Optical Co., Rochester, N. Y. 


5 









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optical work, using a mechanical equipment, consuming the energy of a 
seven hundred horse-power double engine. Steam, gas, compressed air, 
drinking and wash water are distributed in the departments through more 

than seven miles of piping. 
Over five thousand gallons 
of chilled water are required 
per day for washing lenses, 
and over seven hundred gal¬ 
lons of ice-water for drinking 
purposes in the same 'time, 
to cool which an eighteen-ton 
ice machine is in constant 
operation. 

Optical work requires con¬ 
stant and careful inspection. 
To provide against dark days, 
early twilight, and for night 
labor, a complete electric 
lighting plant has been installed, with engine and dynamos, for two thousand 
incandescent and one hundred arc lights, which are fed through ten miles of 
insulated wire. 

Every depart¬ 
ment is in perfect 
communication 
with every other 
department by 

means of the Bell a piece of optical glass thirteen inches thick, and having the two surfaces polished, 
was placed over the calendar and the whole photographed to show 
internal tele- the light transmitting power of the Jena glass. 

phone system, requiring thirty miles of wire and forty telephone stations. 
From the central station one may not only communicate with every part of 
the works, but with every portion of the civilized world reached by tele¬ 
graph, cable, or long-distance telephone. 
These are the nerves and arteries of 
our manufactory, and serve simply to 
outline the extensive equipment of 
delicate and accurate machinery, abso¬ 
lutely necessary in order to produce a 
grade of work which will test up to the 
high optical and mechanical standards 
which we have established. 

Slab c opto. jw.dj.,0 ,«p. tan In makin g the selection of a lens 


The Milling Machine has made it Possible to Duplicate 
Parts with Absolute Accuracy. 


6 


Bausch & Lomb Optical Co., Rochester, N. Y. 















or any other piece of apparatus, the construction and working value of which 
cannot be competently judged except by an expert in the manufacture of 

that particular article, the purchaser is almost 
wholly at the mercy of circumstances unless he 
can, by a knowledge of the methods employed in 
their production, form an estimate of the proba¬ 
bilities in favor of obtaining a perfect article. 
The purpose of this note is to give, in the 
briefest space, a plan of the methods employed 
in our works in making photographic lenses and 
accessories, but especially lenses, since it is 

Piece of optical glass from which the 

lens is ground. regarding the optical qualities of lenses that the 

most extravagant claims are made, and the public has the least chance of 
determining the facts from a superficial examination or test such as is usually 
given before purchase. 

The glass stock vaults contain the choic¬ 
est glass obtainable from all the best glass 
makers of the world, German, French, Eng¬ 
lish— the justly famous Jena glass prepon¬ 
derating. Optical glaSS COmeS from the Lens r °«ghly ground to form, 

makers in square or oblong blocks, each having two small surfaces polished 
on opposite sides, so that each block may be examined and tested before 
any work is done upon it, 
in order that the founda¬ 
tion of the lens may be 
perfect to begin with. The 
first step in the manufac¬ 
ture of a lens is cutting 
the glass, into pieces of 
suitable size by means of a 
diamond saw. The pieces 
are then carefully cement¬ 
ed upon a tool and ground 
roughly to the form the 
lens is to have. These 
partly formed lenses are 

then passed to the skillful The making of Lens Mountings and Iris Diaphragms is an 

. . industry in itself. 

grinder, who grinds the 

surfaces to the exact curvature required by the optical formula which he 
has constantly before him, testing the work at each step with a steel gauge to 
insure its accuracy. This continual testing is rigidly adhered to notwith- 


Branches : New York City and Chicago. 


7 







standing the high degree of manipulative and tactile skill acquired by the 
operatives. The lens now has the correct form and thickness, and is ready 
for that final process in which the highest skill and care are required, the 

polishing. The polish given 
the surfaces of a lens deter¬ 
mines whether the finished 
objective shall give brilliant 
pictures or flat ones, whether 
it shall be slower than its 
ratio of focus to aperture 
indicates it should be, or 
have its normal speed, and 
whether it will retain its 
speed and brilliancy, or grad¬ 
ually lose them. Realizing 
the importance of perfect 
polishing, we have introduced 
the most thorough and ex¬ 
acting system of tests in our polishing department which has ever been 
devised. The foundation of the lens testing system is the test-glass, which 
consists of a block of hard glass having the curvature required for the 
finished lens polished in it absolutely true in every respect. To this curve 
the lens to be tested is fitted. If the lens surface is perfectly true, a series 
of rainbow colored rings (Newton’s rings) will appear from the center to the 
circumference. 

A variation of sWinnr of an inch is instantly detectable by this test, and 
when the extreme delicacy of the test is considered, the reader will begin to 

appreciate the high 
standards which we 
have set for our¬ 
selves, and what it 
means to have the 
guarantee words 

2 Bau 2 C§ & jEoml ©pfxcaf 
Company 

engraved on a piece 
of optical work. The 
tests for thickness, 
freedom from scratches, striae, etc., are equally severe, and the testing is not 
omitted when the lens leaves the polishing department. All the way through 
the various processes, centering, cementing, mounting, assembling, and the 



Circular striation from defective pol¬ 
ishing. Not visible to 
unaided eye. 




In grinding, as in all other processes, the skill and 
patience of individual labor enters into the 
excellence of our lenses. 


Bausch & Lomb Optical Co., Rochester, N. Y. 











finished objective itself, test after test is applied. As the lenses come from 
the final polishing they are perfect as to curvature and thickness, but the 
edges are still rough and the optical center does 
not coincide with the geometrical center. Each 
lens, large or small, must, therefore, be cemented 
on the spindle of a lathe and centered. The first 
operation in centering is to make the optical 
center of the lens coincide with the center of the 
lathe spindle. To do this the workman warms the 
cement and, with a forked wooden tool, presses 
the rapidly revolving lens into the proper position. 

The correct position is determined by watching 
the reflection of a bright object in the lens. 

When the image appears perfectly steady the lens is known to be centered. 
This centering test is an extremely delicate one and requires great dexterity 

and long practice on the part of the operative. 
The lens having been centered, it is turned down 
to the correct diameter with a diamond. 

The centered lenses are then thoroughly 
cleaned and passed to the cementers. Here 
the crown and flint lenses which are to form a 
lens system are carefully warmed to a uniform 
temperature and joined together with a special 
transparent balsamic cement. The utmost care 
is required in this step, as the slightest variation 
in the film of cement or the least decentering 
of any lens in the system would be fatal to its optical perfection. Even so 
apparently slight a thing as a little too much pressure on one side of the lens 
during the cementing may introduce a strain 
which will produce the most disastrous results. 

The cemented combinations have their edges 
carefully sealed with a black impermeable cement, 
and are then ready for mounting. The mount¬ 
ing of a lens does not seem at a glance to be so 
very important, but in reality the mount plays just 
as important a part in the make-up of a good 
photographic objective as the lenses themselves. 

First, the cells in which the lenses are placed 
must be perfectly true and centered to the 
smallest fraction of a millimeter, and the lenses must be fastened in them 
in such a manner as to be held perfectly rigid and true to the axis of the 



Effect of strain in cement. Undetect¬ 
able except by special test. 



Stria in glass. Would not be noticed 
except by an expert glass 
tester. 



Cross striation, from defective polish¬ 
ing, Not visible to the un¬ 
aided eye. 


Branches: New York City and Chicago. 







mount, but at the same time not too tightly, lest the undue tension cause a 
false refraction. The interior of the mount must be so- constructed that the 
full aperture of the lenses shall be utilized and all opportunity for reflections 

destroyed. The distances 
between the lens systems 
must be calculated with ab¬ 
solute accuracy, as the cover¬ 
ing and defining power of 
the objective depends largely 
upon it. Finally, lightness 
combined with rigidity, and 
these with a pleasing and 
compact form, are required. 

The necessity for critical 
testing at every stage is ap¬ 
parent when it is remembered 
. .. .. . ' , ,.... , ..... that a variation of rsta of an 

The final testing—the proof of skillful, patient labor. 

inch in the thickness of some 
lenses impairs the definition of the objectives, that the slightest variation of 
the thickness of the film of cement between the lenses, the slightest decenter¬ 
ing or too tight mounting in the cell, will have the same result, and yet such 
an objective might pass the purchaser’s test. It is always wiser to rely upon 
the products of an institution whose methods 
and principles are known to be the best. 

We are pleased to be able to state that our 
products have been our best and almost our sole 
advertisements in the past, and the fact that there 
are now over 102,000 of our photographic lenses 
in use, is sufficient evidence that the years of 
trial have demonstrated their superior quality to 
the entire satisfaction of the photographic world. 

This enormous number represents only the 
double combination lenses, and does not include the several millions of single 
achromatic and other single lenses which we have made for photographic use. 
When our initial efforts in the production of photographic lenses were made, 
at which time only foreign lenses were in use, it was seriously questioned 
whether lenses could be made in this country. 

As to the production of photographic shutters, of which tens of thousands 
are made annually, the same systematic and careful methods are employed; 
special tools and machinery, comparing in delicacy with those used in watch¬ 
making, are employed throughout.__ 


Effect of minute crack in cement, such 
as would escape ordinary 
examination. 


Bausch & Lomb Optical Co., Rochester, N. Y. 


IO 








IMPROVEMENTS IN LENS MOUNTINGS. 

The mountings for our various lenses have been reconstructed to secure 
the greatest compactness, neatness, and interchangeability. 

We have discarded the unsightly brass hoods formerly employed on the 
front of the lens, except in the very rapid lenses used in portraiture, as large 
hoods are found to be of no real benefit if the lenses and interior of mount 
are properly constructed. Large hoods will, however, be supplied if desired. 

We have applied the iris diaphragm between the combinations of lenses 
whenever it is possible to do so, the smaller sizes of the wide-angle lenses 
only being supplied with revolving diaphragms. 

Although steel is often used for the leaves of the iris diaphragm, they are 
liable to rust or become glossy and thereby create reflections; we prefer 
vulcanite, as it remains permanent. We use a large number of leaves, forming 
a practically round opening, which cannot be obtained otherwise. 

After considerable experience in the use of aluminum we have entirely 
discarded it as unsuitable for the lens cells, and, while we recommend brass 
for the remainder of the mount, will employ aluminum for parts other than 
lens cells if it is desired, at an extra cost. 

All lens mounts are engraved with our name , designation , number of lens , 
and size of plate. This is our guarantee, and every lens so engraved is 
warranted free from optical and mechanical defects. 

ANGLES OF LENSES. 

To avoid any misconception on the part of the purchaser, we give, in 
addition to the angle of the image circle, the exact angle of view of each lens, 
using the long side of the plate for which the lens is rated as the base. It has 
heretofore been customary to use the angle of the whole image circle of a 
lens, or at least that formed with the diagonal of the largest plate the lens 
would cover in designating the angle of a lens. Neither of these gives a 
correct idea of the working angle of the lens. 

NEW APPARATUS. 

The entire series of Bausch & Lomb-Zeiss Anastigmats is retained except 
Series I, and a new one is added under the name of the Bausch & Lomb-Zeiss 
Planar, giving advantages not possessed by any other lenses. 

The popularity of our Iris Diaphragm Shutter is undiminished. We also 
list for the first time our Unicum Shutter, to meet the demand for a more 
simple form. 

The Iconoscope, a perfect finder for all kinds of cameras, is also listed 
for the first time. 

Although our Bichromate of Potash Ray Filters have found their way 
around the world, they have come into existence since our last catalogue was 
issued. 

FOREIGN ORDERS. 

It is gratifying to note that our products are finding favor abroad, where 
there are so many long established manufacturers of optical apparatus. 


Branches : New York City and Chicago. 


Accordingly we have established foreign agencies where our products may be 
obtained. Orders from foreign purchasers not convenient to an agency can 
be filled from our Rochester office. 

DOMESTIC ORDERS. 

The apparatus listed in this catalogue can be obtained from any dealer in 
photographic goods, either in the United States or Canada. Where there is 
any difficulty in obtaining our products through the dealer, we shall be 
pleased to supply them direct at prices as per catalogue. 

LENSES ON APPROVAL. 

We send lenses on ten days’ approval to responsible parties sending 
satisfactory references, or will forward lenses for examination and trial in 
care of the express companies. The purchaser may, if he desires, forward 
the price of the desired apparatus with his order. The goods will then be 
sent on ten days’ trial, and if not wanted, the amount in full will be returned 
on receipt of goods uninjured and charges paid. 

Lenses may be ordered on approval through dealers in photographic 
goods. 

TERMS. 

Parties unknown to us will please send cash with order; or, if desirous 
to open credit account, will please give information and references that will 
enable us to pass upon the matter. 

Checks drawn on banks other than New York, Boston, or Philadelphia 
are subject to collection charges of fifteen cents for amounts less than one 
hundred dollars, or one-eighth of one per cent, for amounts more than one 
hundred dollars, and this sum should be added to remittance. 

When cash accompanies order, and goods are to be sent by mail, add 
amount of postage to remittance , otherwise goods will be sent by express, 
charges collect. Goods sent by mail are at purchaser’s risk. 

Goods will be sent by express C. O. D. only when amounting to more than 
five dollars, express and return charges to be borne by purchaser. One-fourth 
of total amount should accompany order. 


CATALOGUES ISSUED 

BY THE 

BAUSCH & LOMB OPTICAL COMPANY: 


MICROSCOPES, ACCESSORIES, AND LABORATORY SUPPLIES. 
EYEGLASSES AND LENSES. 

BAUSCH & LOMB-ZEISS STEREO FIELD GLASSES. 
PHOTOGRAPHIC LENSES, SHUTTERS, AND ACCESSORIES. 


Bausch & Lomb Optical Co., Rochester, N. Y. 









































OAT/VE BK rf.£.MU#DOCK 


IN MINNESOTA 


Bausch and Lomb-Zeiss 











BAUSCH & LOMB-ZEISS ANASTIGMAT 

LENSES. 


Dr^p^Rudoi^ h ^ ese l enses ) invented by Dr. Rudolph of the firm of Carl 

u p Zeiss, Jena, from whom we have secured the exclusive right to 
manufacture them in America, under American patents, have marked an epoch 
in the construction of photographic lenses. Their optical advantages are so 
pronounced that they were immediately recognized, and are to-day generally 
accepted as the standard photographic lenses. 

Like all meritorious articles, they were followed by imitations, but it is 
self-evident that the knowledge and ability which originated this type of lens 
imitations. must forge ahead of all imitators, no matter how strenuous their 
efforts. This truth is exemplified in the fact that “Zeiss Anastigmat ” is the 
synonym for the “ Best photographic lenses in existence 

The patentees have supplied us with the exact specifications for their 
construction, and keep us fully informed as to all improvements and the 
Material and construction of new types. The high quality of these lenses 
EHrect from " 8 exacts the most critical methods of workmanship in the various 
Zeiss. processes of manufacture and in the final tests. However, our 

long experience in the production of precise optical work, the painstaking 
care which is used, and the systematic control of work at each step of manu¬ 
facture enable us to produce lenses possessing in the highest degree the 
superior optical properties appertaining to this improved construction. 

The advantages of the Zeiss Anastigmat Lenses are: The perfect correctmi 
Points of of astigmatism , astigmatism being a defect inherent in all the 
Superiority. older types of lenses and even in some “ anastigmat ” lenses 
of other makers. 

The proper correction of axial and marginal rays , and the exact coincidence 
and equal magnitude of the visual and chemical images giving sharply defined 
pictures over the entire plate, reproducing straight lines as such and retaining 
the definition with all stops, whichever may have been used to obtain the focus. 

There is no flare spot or ghost to impair the brilliancy of the image, even 
when used under dazzling light. 

The definition being perfect even with large apertures, as a result of the 
elimination of astigmatism and of curvature of the image, lenses of shorter 
focus for a given sized plate may be used, giving greater depth of focus, wide 
angle, and making the lens itself more compact. 

Not The Zeiss Anastigmats, except Series Vila, are not symmetrical 

Symmetrical, lenses in the sense that either of the combinations composing 
them may be used separately for photographic purposes, as it is impossible 
without the use of an additional set of elements to produce a single combina¬ 
tion which will give satisfactory results. 

If one will but give the claims made for lenses of symmetrical construction 
a moment’s consideration, their fallacy will be recognized. Almost all lenses, 
except for studio and technical purposes, are at present used on folding hand 
cameras where compactness is the first consideration. In such cameras there 
is not sufficient bellows extension to permit the use of the rear combination of 
these lenses, as the focus is much longer than in the anastigmats covering the 
same plate. Furthermore, the results obtainable are far from satisfactory, as 
such single combinations not only require microscopic stops to secure defini¬ 
tion, but are even then not at all rectilinear. 

The Zeiss Anastigmat Lenses are the nearest approach to the ideal 
universal lens. 


Branches: New York City and Chicago. 



BAUSCH & LOMB-ZEISS 
PLANAR LENS, SERIES la. 


SPEED f-3.6 

I 



Figure shows the 3X x4)( Series la Lens actual size. 


Description. These objectives are composed of two systems, the outer element 
of each being a single collective lens, and the inner composed of two dispersive 
lenses, having approximately the same refractive, but different dispersive power. 
On account of their extreme rapidity and the consequent large size of the 
lenses, the planars are somewhat heavier than the other anastigmats. 

Optical These lenses reach the extreme limit of rapidity, the speed varying 

Properties. from f-3.6 in the smaller and medium sizes to f-5 in the larger 

sizes. The angle of the image circle is 72 degrees, of which 50 degrees are 
utilized on the small plates for which the lenses are rated. The Planars are 
superior in precision of defining power to any of the other anastigmats. In 
fact, the results obtainable are such as to leave nothing further to be desired. 
Application. In this lens the photo-engraver will find that which he has looked 
in vain for in other lenses, viz., a lens which will give a reproduction equal 
to the copy, from same size down to the smallest reduction. They possess in 

Photo- addition great speed, making them time savers, not only in giving 

Engraving. the best work, but with very short exposure. 

For those difficult and peculiar classes of instantaneous photography 
where speed is the imperative quality, the Planar will be found a great 
ultra Rapid improvement over the extra rapid lenses of other types heretofore 
instantaneous used, as they have speed equal to that of the fastest portrait 
Photography. i enses ^ an( t at the same time a covering power which the others 
have not. For making kinemetograph and other negatives for the projection 
of animated pictures, these lenses are particularly well adapted, the smaller 
sizes having the requisite depth of focus and speed. 


Bausch & Lomb Optical Co., Rochester. N. Y. 


14 














PRICE-LIST 


OF 

Bausch & Lomb-Zeiss Planar Lenses. 

Series la. 


All Lenses are Supplied with Improved Iris Diaphragm and 

Morocco Cap. 


Telegraphic 

Code. 

No. 

Size of Plate 
Covered 
with 

Largest Stop.* 
Inches. 

Equiva¬ 

lent 

Focus. 

Inches. 

Diameter 

of 

Lens. 

Inches. 

Speed. 

Angle. 

Deg. 

Price. 
Lens Only.t 

Plagium 

9 

2 |X 3 i 

45 

ii 

f-3.6 

70 

% 53 00 

Plakoid 

10 

3 t x 3 t 

5 

ii 

f- 3-8 

70 

63 00 

Planeta 

11 

3 t x 4 t 

61 

if 

f-3.8 

70 

77 00 

Planum 

12 

4r x 62 

8 

2 

f— 4 - 

65 

109 00 

Plasma 

J 3 

5x8 

10 

* 

f - 4 - 

65 

150 00 

Plastic 

14 

62 X 82 

12 

2 f 

f—4.2 

62 

192 00 

Plastron 

15 

7x9 

142 

3 ? 

f- 4-5 

7 2 

241 00 

Plata 

16 

8x10 

16! 

35 

f- 4-5 

72 

300 00 

Platanno 

17 

IO X 12 

182 

3 * 

f-s- 

68 

349 00 

PI at inid 

18 

12 X l6 

24 

4 f 

f- 5 - 

68 

698 00 


* The next larger plate is well covered with intermediate stop, 
t Nos. 9, io, ii, and 12 only can be fitted with Iris Diaphragm Shutter. 


Sizes larger or smaller than listed above will be made to order if desired. 

When ordering lenses fitted with shutter by telegraph, specify Diaphragm 
in addition to the code word for the size of the lens. 


Branches: New York City and Chicago. 


T S 





























BAUSCH & LOMB-ZEISS 
ANASTIGMAT LENS, SERIES IE 


SPEED f-6.3 



Figure shows 4x5 Series II Lens actual size. 

Description. The front system of these objectives is composed of two and the 
back system of three lenses. As the systems are necessarily quite large, on 
account of the large aperture, the lens as a whole is somewhat heavy; the 
mounts, however, are reduced in weight in every practical way. The Iris 
Diaphragm shutter may be fitted to all sizes up to and including the 6)4 x 8 ) 4 > 
The sizes larger than 6 j 4 x8^ have an aperture greater than the largest 
opening of the shutter, hence, if fitted with a shutter, the speed would be 
reduced. Special shutters must therefore be used on these larger sizes. 

Optical The speed of this series is f-6.3. Being one of the most rapid 

Properties. of the anastigmats, they are particularly adapted for the fastest 

instantaneous exposures, ordinarily rapid instantaneous work on cloudy days, 
in shaded situations, and in the studio. 

The full angle of the field is 85 degrees, of which 46 degrees are utilized 
on the plates for which the respective sizes are rated. The anastigmatic and 
spherical corrections are of a very high order, especially considering the speed 
and angle. 

Application. Where a lens is to be selected solely on account of great speed, 
instantaneous and where the Vila is too expensive, this lens will be found the 
Photography, best of all anastigmats. 

They possess a further advantage, that they may be used for all ordinary 
purposes by reducing the speed (aperture), thus giving the same covering 
General Work, power and depth of focus which other lenses working under the 
same conditions have. 

The Series II lenses are especially desirable for the studio on account of 
their great speed combined with optical qualities which enable the photog- 
studio. rapher to place sitters for groups in any desired position, and 

does not confine them to the usual semi-circular arrangement in order to 
secure equal definition and size of figures. 


16 


Bausch & Lomb Optical Co., Rochester, N. Y. 


















PRICE-LIST 


OF 

Bausch & Lomb-Zeiss Anastigmat Lenses. 

Series II. 


All Lenses are Supplied with Improved Iris Diaphragm and 
Morocco Cap. 


Telegraphic 

Code. 


Size of Plate 
Covered 

Equiva¬ 

lent 

Focus. 

Inches. 

Free 

Diameter 

Price. 

No. 

with 

Stop f-g.* 
Inches. 

of Largest 
Lens. 

Inches. 

Lens Only. 

When Fitted 
with Diaphragm 
Shutter. 

Zaffer 

I 

2 !X 3 I 

3 * 

5 

8 

$ 3 ° 00 

$ 45 00 

Zany 

2 

3 ^ x 4 r 

4 ? 

3 

¥ 

33 5 ° 

48 50 

Zealous 

3 

4 x 5 

Si 

1 

O 

LO 

O 

55 5 ° 

Zedoary 

4 

4r x 61 

6H 

ii 

5 1 00 

66 00 

Zephyr 

S 

5 x 7 

81 

ItV 

64 50 • 

80 50 

Zigzag 

6 

5 x 8 

9 « 

if 

O 

LO 

00 

96 00 

Zinc 

7 

6hx 81 

nfl 

2 

108 50 

126 00 

Zincky 

8 

8 x 10 

14A 

2! 

150 00 


Zodiac 

9 

10 x 12 

16H 

2xf 

192 00 


Zone 

10 

II x 14 

2 016 

3 * 

240 50 


Zoology 

11 

12 X IS 

2 3 t 

3 « 

300 00 



* The next larger plate is well covered with small stop. 


Price for matching two lenses for stereoscopic work, $3.00. 

For sizes of flanges, see page 66. 

Special sizes of Series II lenses, either larger or smaller than listed above, 
are made to order only. Prices on application. 

When ordering shutters fitted to lenses, by telegraph, specify Diaphragm 
in addition to the code word for the size of lens. 


Branches: New York City and Chicago. 


17 
























BAUSCH & LOMB-ZEISS 
ANASTIGMAT LENS, SERIES I la. 


SPEED f-8 



Figure shows the 5x7 Series Ila Lens actual size. 


Description. The front system of these objectives is composed of two and the 
back system of three lenses, special Jena glass being used. The two systems 
have a greater separation than in the other anastigmat lenses, and therefore 
admit the application of the Iris Diaphragm shutter, as well as the Unicum 
and other shutters which operate between the lenses, to the smaller sizes. 
The mountings are extremely neat and compact. 

Optical These lenses have a speed of f—8 and give ample illumination 

Properties. under unfavorable circumstances. The anastigmatit 'and spherical 

corrections are not equaled in any other lens, except the Series Vila. They 
have therefore unequaled covering power, reproducing the minutest detail 
without the necessity of reducing the aperture, and rendering straight lines at 
all angles and in all parts of the field as such. They have an angular field of 
75 degrees, 6o degrees of which are utilized on the plates for which the 
various sizes are rated. The focus of each lens of the series is shorter for the 
plate for which it is rated, than can be employed with other lenses, thus 
giving greater depth of focus and angle. 

Application. On account of their superior optical qualities, short focus, the 
compactness of the mounting, and the applicability of shutters to them, the 
Hand smaller numbers are better suited for use with hand cameras 

cameras. than any other lenses, excepting only the Series Vila. This is 

also true regarding all the sizes when used for tripod cameras. In fact, they 
General are the best of all the Zeiss Anastigmats where one lens only is 

photography, to serve for all kinds of work. 

In a well lighted studio they are suited for portraits of heads and full 
figures on account of their depth of focus and for groups, as they do not 
studio. require the proverbial semi-circular arrangement in order to 

secure definition and equal size of all figures. 

Severe and practical tests have shown the Series Ila lenses to be well 
Reproductions, suited for copying, on account of faultless reproduction of detail, 
flatness of the field, and the capacity to copy straight lines at all angles. 
They are in everyday use by a large number of photo-engravers. 


18 


Bausch & Lome Optical Co., Rochester, N. Y. 























PRICE-LIST 


OF 

Bausch & Lomb-Zeiss Anastigmat Lenses. 

V 

Series ila. 


All Lenses are Supplied with Improved Iris Diaphragm and 
Morocco Cap. 


Telegraphic 

Code. 

No. 

Size of Plate 
Covered 
with 

Stop f-8.* 
Inches. 

Equiva¬ 

lent 

Focus. 

Inches. 

Free 

Diameter 
of Largest 
Lens. 

Inches. 

Price. 

Lens Only. 

When Fitted 
with Diaphragm 
Shutter. 

Zaba 

I 

4 X 5 

. 3 

4 s 

8 

$ 3 ° 00 

$ 45 00 

Zaccho 

2 

4rx 61 

-3 

5 » 

8 

¥ 

33 5 ° 

48 50 

Zapha 

3 

5x8 

61 

1 

44 00 

59 00 

Zamia 

4 

6|x 8j 

8 

its 

54 5 ° 

69 50 

Zapote 

5 

8x10 

9 * 

IlV 

64 50 

80 50 

Zarmich 

6 

10 x 12 

11I 

T 5 

I 8 

8 5 5 ° 

103 00 

Zax 

7 

11 x 14 

13* 

2 

I2 5 5 ° 

143 00 

Zayah 

8 

14x17 

1 7 

r% 3 

2 8 

160 50 



* The next larger plate is well covered with small stop. 


Price for matching two lenses for stereoscopic work, $3.00. 

See page 66 for sizes of flanges. 

Special sizes of the Series Ila lenses, either larger or smaller than listed 
above, will be made to order only. Prices on application. 

When ordering shutters fitted to lenses, by telegraph, specify Diaphragm 
in addition to the code word for the size of lens. 


Branches: New York City and Chicago. 


19 

















BAUSCH & LOMB-ZEISS 
ANASTIGMAT LENS, SERIES III. 

SPEED f-7.2 



Figure represents the 5x7 Series III Lens actual size. 


Description. The front system of these objectives is composed of two and the 
back system of two lenses, not, however, of symmetrical construction. This 
is the original type of the anastigmat lenses, and embodies the principles of 
correction on which the anastigmats are founded. They are of simpler 
construction than the Series II and Ila. 

Optical The speed of this series is f-7.2. The anastigmatic corrections 

Properties. are not quite equal to the Series Ila and Ilia, but the speed 

being greater, it meets the requirements for a lens between the Series II and 
the Ila and Ilia. 

The field embraces an angle of 85 degrees, about 50 degrees of which 
are intercepted by the plate for which the special sizes are rated. 

Application. The Series III lenses being less in price than the Series II and 
Ila, and still spherically and anastigmatically well corrected, are often pre- 
Generai ferred to the latter, as they are sufficiently rapid for nearly all 

Photography, instantaneous work. 

They are particularly adapted for portraiture and for photographing 
studio. groups, as they do not require the proverbial semi-circular 

arrangement, and for single figures give roundness with excellent definition. 


Bausch & Lomb Optical Co., Rochester, N. Y. 


20 
















PRICE-LIST 


OF 

Bausch & Lomb-Zeiss Anastigmat Lenses. 

Series ill. 


All Lenses are Supplied with Improved Iris Diaphragm and 
Morocco Cap. 


Telegraphic 

Code. 


Size of Plate 
Covered 

Equiva¬ 

lent 

Focus. 

Inches. 

Free 

Diameter 

Price. 

No. 

with 

Stop f- 7 . 2 .* 
Inches. 

of Largest 
Lens. 

Inches. 

Lens Only. 

When Fitted 
with Diaphragm 
Shutter. 

Z untie 

1 

3xx 4 r 

,13 

3*6 

t 

% 24 50 

$ 39 5 ° 

Zurbite 

2 

4x5 

. 3 

4t 

t 

28 00 

43 00 

Zoonic 

3 

4r x 65 

5 it 

I 

3 1 5 ° 

46 50 

Zoolite 

4 

5 x 7 

7 it 

it 

42 00 

57 00 

Zomar 

5 

5x8 

8H 

ife 

5 2 5 ° 

O 

LO 

00 

kO 

Zode 

6 

64 x 84 

9xt 

if 

63 00 

80 50 

Zizel 

7/ 

8x10 

I2T6 

2 

84 00 

101 50 

Zorcon 

8 

10 x 12 

17 * 

o 13 

2 1 6 

i 3 2 5 ° 


Zincode 

9 

12 x 15 

2 3 t 1 <t 

,ii 

3 Tf 

188 50 



* The next larger plate is well covered with small stop. 


Price for matching two lenses for stereoscopic work, $3.00. 

See page 66 for sizes of flanges. 

Special sizes of Series III lenses, either larger or smaller than listed 
above, are made only to order. Prices on application. 

When ordering shutters fitted to lenses, by telegraph, specify Diaphragm 
in addition to the code word for the size of lens. 


Branches : New York City and Chicago. 


















BAUSCH & LOMB-ZEISS 
ANASTIGMAT LENS, SERIES Ilia. 

SPEED f-9 



Figure represents the 5x7 Series Ilia Lens actual size. 


Description. The objectives of this series are composed of four lenses, some¬ 

what less in diameter than the preceding series, therefore lighter and more 
compact. 

Optical Having a speed of f-9, they are suitable for all ordinary instan- 

Properties. taneous work. The anastigmatic corrections are perfect beyond 

the size of plate for which they are rated. The field embraces an angle of 
97 degrees, and about 55 degrees are included by the plates for which the 
various numbers are scheduled. It is therefore practical to use them as 
medium wide-angle lenses on larger plates than those for which they are 
rated, giving perfect definition to the margin, an advantage not possessed by 
any lens of any other make. 

Where a cheaper though somewhat slower lens than series Ila is 
desired for hand camera work, the Ilia is recommended. 

For general photography, they are good outdoor lenses and 
cheaper than Series Ila, and may be used as medium wide 
Photography. an g} e objectives on larger sized plates than those for which 
they are rated. 

stereoscopic The small sizes have the proper angle for stereoscopic work 
Work. with great depth of focus. 


Application. 

Hand 

Cameras. 

General 


Bausch & Lomb Optical Co., Rochester, N. 


22 




















PRICE-LIST 


OF 

Bausch & Lomb-Zeiss Anastigmat Lenses. 
Series ilia. 


All Lenses are Supplied with Improved Iris Diaphragm and 
Morocco Cap. 


Telegraphic 

No. 

Size of Plate 
Covered 

Equiva¬ 

lent 

Focus. 

Inches. 

Free 

Diameter 

Price. 

Code. 

with 

Stop f-g.* 
Inches. 

of Largest 
Lens, 

Inches. 

Lens Only, 

When Fitted 
with Diaphragm 
Shutter. 

Zas 

0 

2fx 3 1 

3 

7 

16 

$ 21 OO 

$ 36 OO 

Zif 

00 

3 * x 4 t 

3 ± 

1 

2 

2 1 OO 

36 OO 

Zinn 

* 

4x5 

4 r 

5 

8 

23 OO 

38 OO 

Zihn 

2 

4I x 61 

5 * 

3 

¥ 

26 50 

41 5 ° 

Zeguel 

3 

5 x 7 

6} 

1 

8 

3 1 5 ° 

46 50 

Zaddow 

4 

5x8 

7 ** 

1 

35 00 

5 ° 00 

Zerial 

5 

61 x 81 

9 A 

ii 

45 5 ° 

60 50 

Zerious 

6 

7x9 

10! 

it% 

56 OO 

72 OO 

Zerf 

7 

8 x 10 

12I 

T 5 

I 8 

70 OO 

86 00 

Zerge 

8 

10 x 12 

16 

2 

105 OO 

122 50 

Zet 

9 

11 x 14 

19! 

2 A 

J 39 5 ° 


Zeton 

10 

12 X15 

231 

2ri 

I 74 5 ° 


Zetto 

11 

14 x 17 

27 A 

3 * 

227 OO 


Zeven 

12 

16 X 20 

3 2 i 

3 ^ 

279 OO 



* Next larger plate is well covered with smaller stop. 

Price for matching two lenses for stereoscopic work, $3.00. 

For size of flanges see page 66. 

Special sizes of Series Ilia lenses, either larger or smaller than listed 
above, are made to order only. Prices on application. 

In using the telegraphic code specify Diaphragm if diaphragm shutter is 
desired, in addition to the code word for the size of lens. 

Branches: New York City and Chicago, 


23 





















BAUSCH & LOMB-ZEISS 
ANASTIGMAT LENS, SERIES IV. 

SPEED f-12.5 



Figure shows 5x8 Series IV Lens actual size. 


Description. These are very compact objectives, each system being composed 
of two lenses. The two systems are not, however, of the same focus, hence 
not usable as single lenses. The improved Jena glass is used in this as 
in the other anastigmats. 

The mountings are all fitted with Iris Diaphragm, except the two smaller 
sizes, in which the systems are so close together that the revolving diaphragm 
only can be used. 

Optical The speed is f-12.5, which is fast enough for outdoor instanta- 

Properties. neous work under favorable circumstances. The field of the first 

six numbers embraces an angle of over 100 degrees. They give an angle of 
68 degrees on the long side of the plates for which they are rated. The full 
angle of the larger numbers is 85 degrees, of which 44 degrees are utilized on 
the plates for which they are listed. 

Application. For rapid wide-angle work or where architectural or other subjects 

instantaneous are to be photographed instantly, and where the distance from 
Wide-angle , . . . . , , , , 

photography, the camera is such as to require a wide-angle lens, the first six 
numbers are recommended. 

Flash-light Interior photography, where a rapid lens is desired, as for dash- 
interiors. light work, and still a wide angle required. 

Either enlarging or reducing. The five larger sizes are designed 
Reproductions, especially for copying, and are of less aperture than the smaller 
numbers of the series. 


Bausch & Lomb Optical Co., Rochester, N. Y. 


24 














PRICE-LIST 


OF 

Bausch & Lomb-Zeiss Anastigmat Lenses. 
Series IV. 


All Lenses are Supplied with Improved Iris Diaphragm and 
Morocco Cap. 


Telegraphic 

Code. 

No. 

Size of Plate 
Covered 
with 

Stop f- 1 . 5 .* 
Inches. 

Equiva¬ 

lent 

Focus. 

Inches. 

Free 

Diameter 
of Largest 
Lens. 
Inches. 

Price. 

Lens Only. 

Zibet 

I 

3 * x 4 t 

2 A 

1 

¥ 

$ 1 7 5 ° 

Zend 

2 

4 X 5 

38 

3 

8 

1 7 5 ° 

Zoffer 

3 

4 ix 61 

4II 

1 

21 00 

Zein 

4 

5x8 

6 t 6 

1 

24 50 

Zirco 7 i 

5 

8 x 10 

lii 

It 

3 1 5 ° 

Zoril 

6 

10 x 12 

io* 

1 

47 00 

Zennir 

7 

12 X15 

15x6 

1 X 6 

7 1 5 ° 

Zofil 

8 

16 X 20 

23 1 6 

2 

I2 5 5 ° 

Zodic 

9 

20 X 24 

- r ll 

35 i« 

2 It 

282 50 

Zunn 

IO 

24 X30 

481 

38 

631 00 


* The next larger plate is well covered with smaller stop. 


For sizes of flanges, see page 66. 

In using the telegraphic code specify Diaphragm if the Iris Diaphragm 
shutter is desired fitted to the lens, in addition to the code word for the size 
of lens. 


Branches: New York City and Chicago. 















BAUSCH & LOMB-ZEISS 
ANASTIGMAT LENS, SERIES V. 

SPEED f—IS 



Figure shows 8x10 Series V Lens actual size. 


Description. The two dissymmetrical systems are composed of two lenses each. 
Being small and very close together, the objectives are the most compact 
possible to construct. The mountings are fitted with the Iris Diaphragm, 
except in the two smaller sizes, where the systems are so close together that 
the revolving diaphragm only can be used. 

Optical The speed of the lenses of this series is f—18. The field embraces 

Properties. an angle of no degrees in the sizes up to and including No. 7a. 
The full angle of the lenses above No. 7a is 90 degrees. On the plate for 
which the smaller numbers are rated, the angle is 75 degrees, but the full 
angle may be obtained by using them on larger plates with smaller stops. 
The larger sizes have an angle of about 40 degrees on the plates for which 
they are listed. The anastigmatic and spherical corrections are the most 
perfect yet obtained in a wide-angle lens, and the images are entirely free 
from distortion to the margin of the plate even with the most extreme angle. 
Application. The lenses of this series are without question the most desirable 
Extreme wide-angle lenses made, and should be selected wherever an 

Wide-angle & . , , . . , , 

Work. extreme wide angle is required. They have greater speed and 
covering power and greater effective angle than any other extreme wide-angle 
lens, and are at the same time much more compact. 

Copying. The larger sizes were designed especially for copying, and for that 
purpose cannot be equaled in the quality of work which they will do. They 
are, however, not quite rapid enough for some kinds of photo-engraving. 


Bausch & Lome Optical Co., Rochester, N. Y. 


26 









PRICE-LIST 


OF 

Bausch & Lomb-Zeiss Anastigmat Lenses. 

Series v. 


All Lenses are supplied with Improved Iris Diaphragm 
and Morocco Cap. 


T elegraphic 

No. 

Size of Plate 
Covered 

Equiva- 

Free 

Diameter 
of Largest 
Lens. 
Inches. 

Price. 

Code. 

with 

Stop f-18.* 
Inches. 

Focns. 

Inches. 

Lens Only. 

When Fitted 
with Diaphragm 
Shutter. 

Zambo 

I- 

4IX 6| 

-3 

3 s 

A 

$ 22 50 


Zanite 

2 

5 x 7 

. 3 

4-8 

t 

22 50 


Zeal 

3 

6t x 8t 

r- 9 

5^6 

2 

28 00 

$ 43 OO 

Zebra 

4 

8x10 

H 3 

7rtr 

A 

35 00 

5 ° 00 

Zebu 

5 

10 x 12 

8t 

1 1 

T(> 

44 00 

59 00 

Zealot 

6 

11 x 14 

IOt% 

1 3 

54 5 ° 

69 50 

Zenith 

7 

12 xi 5 

I2x<r 

1 5 

TT 

64 50 

79 5 ° 

Zet 

7 a 

16 x 18 

x r- 3 

x 5 3 

1 

75 00 

90 00 

Zulo 

8 

12 x 15 

i8i 

1 

85 5 ° 

100 50 

Zero 

9 

16 X 18 

24I 

it 

I2 5 5 ° 

141 50 

Zest 

10 

20 X 25 

37 * 

2 j 

247 5 ° 



* The next larger plate is covered with small stop. 


Special sizes of Series Y lenses, either larger or smaller than listed 
above, will be made to order only. Prices on application. 

See page 66 for sizes of flanges. 

When ordering shutter fitted to lenses, by telegraph, specify Diaphragm 
if the Iris Diaphragm shutter is desired, in addition to the code word for the 
size of lens. 


Branches: New York City and Chicago. 


27 















BAUSCH & LOMB-ZEISS 
ANASTIGMAT LENS, SERIES VII. 

SINGLE ANASTIGMATS. 

SPEED f—12.5 



Figure shows No. 1, Series VII Lens actual size. 


Description. The single anastigmatic system is composed of four elementary 
lenses (two pairs) cemented together. The lens system is mounted in a sep¬ 
arate adapter of standard size, which fits either end of the tube of the mount. 
This construction has been adopted to carry out the original design of the 
inventor of this remarkable lens, viz.: the combination of two systems of the 
same or different foci, each of which is in itself a perfect anastigmat, to form 
a doublet of extreme speed and angle. A Series VII single anastigmat 
consists of one lens system in an adapter as described above, and a mounting 
into which the lens system fits (see figure). The mounting is provided with 
Iris Diaphragm. The diaphragm apertures (stop numbers) are engraved in 
U. S. numbers on a movable ring, which may bear numbers for two or more 
single anastigmats of different foci, and also for their combined focus. Each 
system has a serial number and the focal length engraved upon it for 
reference. 

Optical The history of lenses shows the invention, trial, and decadence 

Properties. of a large number of “ all purpose ” lenses, i. e., doublets in which 

it was sought to produce single systems of sufficient covering power to be 
usable separately, and which, when combined, would produce a good doublet 


Bausch & Lomb Optical Co., Rochester, 





of greater speed and angle. Some of these lenses are still offered, but they 
will be found unsatisfactory for the reason that the astigmatism and spherical 

distortion inherent in all single 
systems of the symmetrical type of 
lens, are impossible of elimination 
except by the method devised by 
Correction. Dr. Rudolph for the 
single anastigmats, viz., the anas- 
tigmatic correction of the single 
systems according to the same 
principles employed in the correc¬ 
tion of the preceding systems of 
doublets. The increase in the 
number of lenses and the develop¬ 
ment of suitable glass has made it 
possible to apply these principles in the single anastigmats with much more 
satisfactory results than is possible where a less number is employed. 

Speed. The speed of the single anastigmats is f-12.5. 

Angie. The field has an angle 

of 85 degrees, of which from 35 to 
48 degrees are utilized on the plates 
for which each size is listed. 

The images given are anastig- 
matic, very flat, *and with almost no 
distortion, the little which does exist 
being detectable only in that por¬ 
tion of the image circle outside of 
the area included by the plate for 
which each size is listed. 

Application. While it is not intend¬ 
ed that the single anastigmats shall 
take the place of the more rapid 
and wider angle doublets, they form the basis for the Series Vila Convertible 
Landscape Anastigmats, and have in addition a distinct field of their own, 
Photography. j n th a t ; when used singly, they give the most excellent results 

as landscape lenses, the ratio of 
focus to diagonal of plate for each 
number being considerably greater 
than that of the doublet lenses com¬ 
monly used for all around work. 

The speed is sufficient for in¬ 
stantaneous exposures under favor¬ 
able circumstances. 

Group Work. For outside group work 
they are also excellent, giving neg¬ 
atives of great brilliancy and beau¬ 
tiful definition, with agreeable per¬ 
spective. 

Rranches : New York City and Chicago. 



Fig. 3. 

Made with Front Combination of 7-in Convertible 
Anastigmat Lens, from same position as Fig. 1. 



Fig. 2. 

Made with Back Combination of 7-in. Convertible 
Anastigmat Lens from same position as Fig. 1. 



Fig. 1. 

Made with a 7-in. Focus Convertible Anastigmat Lens. 


29 

























PRICE-LIST 


OF 

Bausch & Lomb-Zeiss Single Anastigmat 

Lenses. 

SERIES VII. 


All Lenses are Supplied with Improved Iris Diaphragm and 

Morocco Cap. 


Telegraphic 

Code. 


Size of Plate 
Covered 

Equiva¬ 

lent 

Focus. 

Inches. 

Back 

Diameter 

of 

Diam. 

of 

Image. 

Inches. 

Price. 

No. 

with 

Stop f-12.5.* 
Inches. 

Focus. 

Inches. 

Front 

Lens. 

Inches. 

Lens Only. 

When Pitted 
with 

Diaphragm 

Shutter. 

Acacia 

1 

4 tX 61 

7i 

8 

5 

8 

I I 

$ 26 

5 ° 

$41 5 ° 

A carina 

2 

5 

x 7 

9 

9 i 

3 

¥ 

J 3 * 

3 ° 

00 

45 00 

Aceton 

3 


X 81 

iil 

1 21 

1 

171 

35 

00 

50 00 

Achilles 

4 

8 

x 10 

14 

J 5 * 

ii 

21} 

42 

00 

O 

O 

LO 

Acidalia 

5 

10 

X I 2 

16! 

m 

ii 

2 5 

54 

5 ° 

70 50 

A conit urn 

6 

11 

x 14 

191 

2 ii 

it 

2 9 

75 

00 

9 2 5 ° 

Adinol 

7 

12 

X 16 

23* 

261 

2 

35 * 

96 

00 


Aeneas 

8 

1 3 

X 16 

27 ! 

3 °* 

2! 

, T i 
4 1 4 

I2 5 

5 ° 


Aeolus 

9 

16 

X 18 

3 °i 

34 

2 ? 

47 * 

r 74 

5 ° 


Aequator 

10 

16 

X 20 

34 

37 * 

3 * 

5 2 

227 

00 


Aether 

11 

18 

X 22 

39 * 

43 * 

3 * 

60 

296 

5 ° 



*The next larger plate is well covered with small stop. 


When ordering by telegraph it is sufficient to use the code word placed opposite the 
number. 

When ordering shutters fitted to lenses, by telegraph, specify Diaphragm when the Iris 
Diaphragm shutter is desired, in addition to the code word for the size of lens. 

For sizes of flanges, see page 66. 

The mountings of these lenses are provided with a revolvable ring, engraved with the 
F value of each of the Single and of the Doublet combinations. 

If an additional combination is purchased, the graduated ring is exchanged for another 
engraved with scales for all of the combinations. A stop fixes the scale in the proper 
position. 

When ordering an additional Single combination, give the serial number of the lens 
with which it is to be used. 

When the Single combination is desired without mounting, an allowance of $1.50 will 
be made on numbers 1-5, and $3.00 for numbers 6-10. 

Nos. 1, 2, and 3 fit the same mount, and each larger size requires a succeedingly 
larger mount; all sizes below any given size can, however, be fitted for that mount if desired. 


Bausch & Lomb Optical Co., Rochester, N. Y. 


























BAUSCH & LOMB-ZEISS 
CONVERTIBLE ANASTIGMAT LENS 
Series Vila. 

QUADRUPLE ANASTIGMATS. 

SPEED f-6.3 



Description. The Convertible Anastigmats are doublet lenses composed of two 
of the single anastigmats, Series VII. They contain eight elementary lenses 
arranged in pairs, two pairs in each system. They may therefore be properly 
termed quadruple anastigmats. Such a lens is convertible into three lenses 
of different foci and angle where the two single anastigmats are of different 
foci, or into two where they are of the same foci. 

The most practical combinations of single anastigmats are indicated in 
the appended table of Series Vila lenses. 

Optical The speed when composed of two single anastigmats of the same 

Properties. foci is f-6.3. When the single anastigmats are of different 

foci, the speed is f-7 or f—7.7, according to the relative foci employed. 

The full angle of the image circle is 80 degrees. The average angle 
utilized on the size plate for which the numbers are commonly used is about 
55 degrees. 

As might be expected from the excellence of the single anastigmats, the 
Convertible Anastigmats formed by combining two of them are simply per¬ 
fection in all the qualities which are desired in a photographic lens. The 
covering and defining power is faultless. All parts of the image circle are 
equally well corrected. It is possible, therefore, to use, and still retain the 
large aperture, lenses of much shorter foci than where the optical properties 
are of a lower order, hence the great depth of focus and angle which the 
members of this series possess. 

Branches: New York City and Chicago. 


31 









Astigmatism is entirely eliminated, and as an example of the mathematical 
perfection of the image, we cite the fact that the Series Vila lenses are now 
used in the delicate work of copying bank check, certificate, and bond engrav¬ 
ings, the lines of which are very fine and run at every conceivable angle. 
Such perfection not only yields excellent results in ordinary photography 
under adverse circumstances, but adds that much desired brilliancy to all the 
work of the lens. 

Application. The photographer who essays all classes of subjects with one lens 
only, whatever the focus of that lens may be, will surely be disappointed in 
many ways. 

The long-focus lens which gives the most pleasing landscapes will fail 
utterly for photographing a moving object. Examples of this kind might be 
cited indefinitely. On the other hand, the multiplicity of lenses, front boards, 
flanges, shutters, cases, caps, etc., which the photographer is forced to carry 
about with him in order to have a “ complete equipment ” in the ordinary 
sense of the word, is almost equally unfortunate. The problem is solved by 
the Convertible Anastigmat, as each of its systems may be used singly for 
Typical work requiring a long or medium long focus, low or medium angle 

Universal and medium speed, while the combined systems give an extra 

rapid lens of wide angle suitable for the fastest instantaneous 
exposures, the most difficult architectural subjects, and for any situation where 
speed, angle, covering power, depth of focus, and brilliancy are required. By 
the addition of one single anastigmat to a Series Vila lens, six lenses, three 
single and three doublets, each having different angle, focus, and covering 
power, may be obtained. 

The addition of two single anastigmats to a Series Vila lens, gives ten 
different lenses, four single and six doublets. 

The advantages of the convertible features of the Series Vila lenses may 
be summed up as follows: 

Every doublet is in reality three lenses, each perfectly adapted for a 
separate kind of work. 

The addition of one system adds three lenses, making six in all. 

The addition of two systems adds seven lenses, making ten in alL 

The greatest possible compactness is secured. 

The least weight. 

The fewest parts to lose or wear out. 

For hand cameras these lenses stand at the head of the list both in optical 
Hand qualities and in their adaptability to the limited space allowed for 

Cameras. the lens. In selecting the lens see that the back focus of no 

combination selected is longer than the greatest extension of which the bellows 
is capable. 

The Series Vila Anastigmats in which the two systems are of the same 
foci, and especially the larger sizes, are well adapted for process work and 
Photo- copying of all kinds. The fact that they are now in use by many 

Engraving. prominent photo-engravers, and give universal satisfaction, is the 
best evidence of their excellence. 


Bausch & Lome Optical Co., Rochester, N. Y. 


3 2 


PRICE-LIST 


OF 

Convertible Anastigmat Lenses. 
Series Vila. 


Telegraphic 

Code. 

No. 

Size 

in Inches of 
Plate 

Covered with 
Full 

Aperture .* 

Combinations of 
Single 

Anastigmats. 

Focus. 

Com¬ 

bined 

Equiva¬ 

lent 

Focus. 

Inches. 

Speed. 

Diame¬ 

ter 

of 

Image 

Inches. 

Price. 

Lens Only. 

When Fitted 
with 

Diaphragm 

Shutter. 

Front 

Lens. 

Back 

Lens. 

Agonie 

I 

3 l x 

3 t 

7 i 

7 \ 

4 i 

f-6. 3 

6 f 

O 

O 

BO 

$ 66 00 

Alabaster 

2 

54 x 

4 i 

9 

7 \ 

42 

f -7 

7 i 

54 5 ° 

69 50 

Alauda 

3 

4 x 

5 

°2 

7 i 

5 

f-7. 7 

H 

59 5 ° 

74 5 ° 

Albatros 

4 

4 x 

5 

9 

9 

5 

f-6. 3 

81 

58 00 

73 00 

Alizarin 

5 

4 i x 


“2 

9 

51 

f -7 

92 

63 00 

78 00 

Alkaloid 

6 

4 J X 

62 

14 

9 


f- 7 - 7 

I°2 

70 00 

85 00 

Alkohol 

7 

4 i x 

7 i 

IJ 2 

ni 

^2 

f-6. 3 

iof 

68 00 

83 00 

Amidon 

8 

5 x 

72 

14 

XI 2 

7 

f -7 

12 

75 00 

90 00 

Ananas 

9 

5 x 

82 

l 61 

1 *2 

72 

f-7. 7 

I2f 

87 5 ° 

103 5 ° 

Anchovis 

10 

5 x 

8 * 

14 

14 

8 

f-6. 3 

J 3 i 

82 00 

O 

O 

O 

A nili?i 

11 

61 x 

&2 

x6| 

14 

8* 

f -7 

I 4 | 

94 5 ° 

no 50 

Anthracit 

12 

6 Jx 

8 * 

J 9 i 

14 

9 t 

f- 7 - 7 


115 5 ° 

U) 

O 

O 

Antimon 

*3 

61 x 

8| 

i6i 

16^ 

9 t 

f-6. 3 

i 5 l 

106 50 

122 50 

A ntipyrin 

14 

7 x 

9 

l 9 i 

l6 

IO 

f -7 

i6f 

127 50 

145 00 

Apostat 

!5 

7 x 

9 

232 

l6^ 

11 

f- 7 - 7 

i8i 

148 50 

166 00 

A ristos 

16 

7 x 

9 

J 9 i 

J 9 i 

11 

f-6. 3 

i8i 

146 50 

164 00 

As best 

17 

8 x 

IO 

2 3 i 

J 9 i 

12 

f -7 

20 

167 50 

185 00 

Athene 

18 

8 x 

IO 

272 

l 9 i 

I2f 

f- 7 - 7 

21 2 

197 00 

214 50 

Atlas 

*9 

8 x 

IO 

232 

232 

l 3 i 

f-6. 3 

22\ 

188 50 

206 00 

Atropin 

20 

10 X 

12 

27I 

232 

142 

f -7 

24 

O 

O 

00 


Aurora 

22 

10 X 

12 

272 

272 

x 5 i 

f-6. 3 

26 

247 5 ° 


Autor 

2 5 

IO X 

12 

3 °f 

3 °l 

I8i 

f-6. 3 

26 

345 5 ° 


A zoflavin 

28 

II X 

H 

34 

34 

20I 

f-6. 3 

28I 

45 ° 00 


Azurin 

3 ° 

12 X 

16 

392 

39 i 

■7 'll. 

* 02 

f-6. 3 

3 1 ! 

5 S 9 5 ° 



* The next larger plate is covered with smaller stop. 


The mountings of these lenses are provided with a revolvable ring, engraved with the 
F value of each of the Single and of the Doublet Combinations. 

The correct stop for each of the lenses is thus always read from the scale, exactly as in 
the case of a simple lens. 

If an additional combination is purchased, the graduated ring is exchanged for another, 
engraved with scales for all the combinations. 

When ordering an additional Single Combination, give the number of the lens with 
which it is to be used. 

Nos. i, 2, 3, 4, 5, and 7, when desired for hand cameras, are mounted in special compact 
mountings, and the 4x5 Iris Diaphragm Shutter can then be fitted to them, in which case 
a reduction of $1.00 is made from the listed price of the respective sizes fitted with Iris 
Diaphragm Shutter. 

Branches: New York City and Chicago. 


33 
































SETS OF BAUSCH & LOMB-ZEISS CONVERTIBLE 

ANASTIGMATS. 


While a large number of doublet combinations are listed, having their 
uses for the same purposes as other doublet lenses, there are two sets of the 
Single Anastigmats which practically cover the entire field. 

These sets are offered complete with the lenses mounted interchangeably, 
each set consisting of: 

One lens mount with iris diaphragm, cap, and flange, as described under 
Series VII. 

The Single Anastigmat Lenses (three or four as the case may be). 

A neat and compact morocco case containing all the parts of the set. 


C SET OF ANASTIGMATS. 

Complete in case, $103.00. Code word, Alpha. 

C set of anastigmats fitted with Iris Diaphragm Shutter, $118.00. 

The six lenses which may be formed with the C set of anastigmats are 
shown in the accompanying table, together with their angles, covering power, 
and speeds. 


SERIES. 

No. 

Size of Plate 
Covered with 
Largest Stop.* 

Inches. 

Equivalent Focus of Lenses 
in Inches. 

Speed. 

Angle on 

Plate. 

Degrees. 

Front 

Lens. 

Back 

Lens. 

Combined 

Focus. 

( 


5x8 


9 


f-12.5 

48 

VII. 

) 

) 3 

6|x 8 i 


11 I 


f-12.5 

3 8 

( 

' 4 

8 x 10 


14 


f-12.5 

3 2 

( 

' 5 

4ix 6| 

Ill 

9 

5-4 

f- 7.0 

70 

Vila. 

> 6 

) 

5 x 7 

14 

9 

6| 

f- 7.7 

65 

1 

' 8 

5x8 

14 

11 I 

7 

f— 7.0 

59 


* The next larger plate is well covered with smaller stop. 


Bausch & Lome Optical Co., Rochester. N. Y. 


34 




















D SET OF ANASTIGMATS 


Complete in case, $ 200.00. Code word, Alphabet. 

D set of anastigmats fitted with Iris Diaphragm Shutter, $217.50. 

The lenses of this set are the numbers 3, 4, 5, and 6 of Series VII. 

The following table shows the ten lenses which may be formed with this 
set, together with their angles, covering power, and speed. 


SERIES. 

No. 

Size of Plate 
Covered with 
Largest Stop.* 

Inches. 

Equivalent Focus of Lenses 
in Inches. 

Largest 

Stop. 

Angle on 

8 x 10 
Plate. 

Degrees. 



Front 

Lens. 

Back 

Lens. 

Combined 

Focus. 

( 

3 

6| X 8| 


Ill 


f-12.5 

47 

VII. < 

) 4 

8x10 


14 


f-12.5 

39 

i 

5 

IO X 12 


l6| 


f 1 2 • 5 

34 

I 

6 

ii x 14 


19! 


f-12.5 

29 


8 

5x8 

14 

Ill 

7 

f- 7.0 

7 1 


, 9 

5 X8 

161 

III 

7* 

f- 7.7 

67 


9 a 

5 x 8 

19? 

III 

8 

f- 7.7 

64 

Vila. 

\ 11 

6|x 8| 

16I 

14 

8| 

f- 7.0 

61 

I 

12 

65 x 81 

19I 

14 

9I 

f- 7.7 

57 

1 

1 - 

8 x 10 

191- 

16I 

10 

f— 7.0 

53 


* The next larger plate is well covered with small stop. 



Made with Iris Diaphragm Shutter. 


Branches : New York City and Chicago. 


35 


































UNIVERSAL PORTRAIT LENS, SERIES A. 


SPEED f-4 



Figure shows the No. 2 Universal Portrait Lens one-fourth actual size. 


Description. These lenses are composed of two systems, the elementary lenses 
of the front system being cemented together, while those of the back system 
are separated. The rear lens is mounted in an adjustable mounting, per¬ 
mitting correction of the lens by the operator. 

All sizes are provided with improved iris diaphragm. 

Optical The speed of these lenses being f-4, they are suited for the most 

Properties. rapid studio work. Optically they possess those special requisites 

which make a portrait lens, and which exist only to a very indifferent degree 
in lenses constructed for other work. 

The lenses as sent from our factory are corrected to give the greatest 
sharpness, as required for small portraits. For large portraits, where the 
sitter is near the lens, a greater depth and equality of definition is obtained 
by separating the back lenses by means of the adjustable mounting. In this 
manner any desired softness, roundness, or distribution of focus may be 
obtained. In addition to the above qualities, these lenses have unusual 
freedom from distortion, and even illumination. 

Application. For portrait work only, these lenses are unequaled. They were 
designed solely for this purpose, and the favorable reception they have had 
Portrait a t the hands of the most expert and well-known photographers, 
Photography. p roves that they meet the requirements. 

The number three of this series is especially recommended for cabinet 
work. 

Testimonials on application. 


36 


Bausch & Lomb Optical Co., Rochester, N. Y. 









































PRICE-LIST 


OF 

Universal Portrait Lenses. 

Series a. 


T elegraphic 
Code. 

No. 

Size. 

Inches. 

Diameter of 
Lenses. 
Inches. 

Equivalent 

Focus. 

Inches. 

Price. 

Uberty 

i 

4X5 

2 % 

0 

6| 

$ 65 00 

Udal 

2 

00 

X 

CO 

3z 

SI 

90 00 

Udaler 

3 

6 \x 8| 

4-i 


135 00 

Udder 

4 

8x10 

4-i 

T 3l 

190 00 


Branches: New York City and Chicago. 















EXTRA RAPID UNIVERSAL LENS, SERIES D. 

SPEED f-6 



Figure shows 3 >jf x 4 % Series D Lens actual size. 


Description. This is the extra rapid type of rectilinear lens, the front and 
back systems being each composed of two lenses cemented together. 

The lenses are of large diameter, but, being quite thin, do not increase the 
weight of the lens appreciably. The mounting is very compact. 

Optical The speed of the lens is f-6. 

Properties. The image circle embraces an angle of 70 degrees. 

This series represents the best of the rectilinear type of lenses, in speed, 
covering power, and depth of focus. 

Application. Thousands of photographers in all branches are to-day using this 
excellent lens, and, while it does not equal the anastigmats in all respects, it is 
General Work, a good and serviceable lens for general work, has sufficient speed 
for the most rapid instantaneous work and a decided advantage in price. 

The compactness, speed, depth of focus, and moderate price recommend 
Hand the smaller sizes for hand cameras, while its speed is greater 

cameras. than necessary under ordinary conditions. Ample exposure is 

obtained on dark and misty days where other slower lenses would fail, 
studio. For studio work this lens will be found especially satisfactory, as 

the field and focus, especially in the larger sizes, are admirably suited for 
portraiture, and it has sufficient covering power for excellent group work. 

The speed, f-6, is sufficient for all occasions, as the rapid plates now in 
general use do not require a more rapid lens in the studio. These lenses are 
now in use in many of the best known studios. 


38. 


Bausch & Lome Optical Co., Rochester, N. Y. 




















PRICE-LIST 


OF 

Extra Rapid Universal Lenses. 
SERIES D. 


All Lenses are Supplied with Improved Iris Diaphragm and 
Morocco Cap. 


Telegraphic 

Code. 

No. 

Size of 
Plate. 

Inches. 

Diameter 

of 

Lenses. 

Inches. 

Equiva¬ 

lent 

Focus. 

Inches. 

Back 

Focus. 

Inches. 

Price. 

Lens Only. 

Lens with 
Diaphragm 
Shutter. 

Ukase 

o 

4 i 

I 

4 t 

3 ft 

$> 24 00 

$ 39 OO 

Ulaus 

oo 

4x5 

if 

6f 

5 A 

28 OO 

43 00 

Ulcer 

I 

5x8 

ii 

8 

7 

36 00 

5 1 00 

Ulema 

2 

6f x 8i 

if 

9rs' 

8f 

46 00 

62 00 

Ulnim 

3 

8x10 

2 j 

nf 

9ft 

58 00 

75 5 ° 

UInage 

4 

10 x 12 

2f 

i 4 f 

12^6 

75 00 


Umbel 

5 

12 x 15 

3 * 

i 7 f 

r 5 f 

100 00 


Umber 

6 

16 x 20 

3 * 

22! 

19! 

130 00 



When ordering lenses fitted with shutter, specify Diaphragm , in addition 
to the code word for the size of lens. 

Testimonials from prominent photographers on application. 


Branches: New York City and Chicago. 


39 

















RAPID UNIVERSAL LENS. 


SPEED f-8 



Figure shows the Rapid Universal Lens 4x5 actual size. 


Description. This is our original rapid rectilinear type lens, the front and 
back systems being similar and composed of two lenses each. The mount¬ 
ings are now reduced in size and made as compact as possible in accordance 
with modern requirements. 

Optical The speed of these lenses is f-8. The angle of the image circle 

Properties. is 70 degrees. 

Application. This is the lens which a large majority of all amateur photog¬ 
raphers have used up to 1896, and which a very large number are still buying 
General and us i n g- It has excellent covering power, and sufficient speed 

Photography. f or a p ordinary uses. The focus is such as' to give a most 
agreeable perspective. The moderate price places a really good lens in the 
hands of those who cannot afford an anastigmat. 


Bausch & Lomb Optical Co., Rochester, 
























PRICE-LIST 


OF 

Rapid Universal Lenses. 


All Lenses are Supplied with Improved Iris Diaphragm and 
Morocco Cap. 


Telegraphic 

Code. 

No. 

Large Stop 
Covers. 

Equiv¬ 

alent 

Focus. 

Inches. 

Diameter 
of Image 
Circle. 

Inches. 

Diameter 

of 

Lenses. 

Inches. 

Back 

Focus. 

Inches. 

Price. 

Lens Only. 

When Fitted 
with 

Diaphragm 

Shutter. 

Ucubis 

4 -i 

3 * x 4 i 

5 * 

8 

1 

. 3 

4 t 

$ 18 00 

$33 00 

Umbria 

5 

4x5 

6! 

9 * 

1X6 

H 3 

5 ? 

22 00 

37 00 

Unca 

8 

5x8 

81 

11 

if 

7 t 

26 00 

41 00 

U?ielli 

81 

6 k x 8 k 

nf 

1 3 i 

if 

iof 

35 00 

5 1 00 

Upis 

10 

8 x 10 

1 3 i 

15* 

if 

I 2 f 

48 00 

6 5 5 ° 

Uraca 

12 

10 x 12 

*7 

20 

2j 


60 00 


Uxantis 

*5 

12 x 15 

2 oi 

21k 

2 8 

18 

75 00 


Utica 

18 

16 x 18 

24! 

27 k 

3 * 

22 f 

95 00 


Uzita 

22 

20 X 22 

3 *f 

3 6 

4 i 

28 

125 00 



When ordering lenses fitted with Iris Diaphragm Shutter by telegraph, 
specify Diaphragm in addition to the code word for size of lens. 


Branches: New York City and Chicago. 


41 


















ALVAN G. CLARK LENS. 


SPEED f-8 



Figure shows the 4x5 Alvan G. Clark Lens actual size. 


Description. These lenses are the invention of the late Alvan G. Clark, maker 
of the famous Clark telescopes, and differ from the rapid rectilinear type of 
lens, in that none of the lenses are cemented, and that the hardest glass is 
placed outermost; hence the lenses will never degenerate, or become slower, 
and are less liable to become scratched. The mountings are more compact 
than in the rectilinear lenses, as the systems are closer together. 

Optical The speed is f-8. 

Properties. The angle of the image circle is ioo degrees. 

They are well corrected objectives, and have given satisfaction to a large 
number of photographers. 

Application. They are applicable to all work for which the rectilinear type of 
lens is adapted, and possess the advantage over many in that they may be 
used for medium wide-angle work also. 


Bausch & Lomb Optical Co., Rochester, N Y. 

























PRICE-LIST 


OF 

Alvan G. Clark Lenses. 


All Lenses are Supplied with Improved Iris Diaphragm and 

Morocco Cap. 


Telegraphic 

Code. 

No. 

Size of Plate 
Covered 
with 

Largest Stop. 

Inches. 

Equiv¬ 

alent 

Focus. 

Inches. 

Diameter 
of Image 
Circle. 

Inches. 

Diameter 

of 

Lenses. 

Inches. 

Back 

Focus. 

Inches. 

Price. 

Lens Only. 

When Fitted 
with 

Diaphragm 

Shutter. 

Abel 

4 -i 

3 ? x 4 ? 

5 * 

81 

1 

. 3 

4 ? 

$ 20 OO 

$ 35 00 

Abner 

5 

4x5 

61 

I 3 

1 

r- 3 

5 * 

24 OO 

39 00 

A chan 

8 

5x8 

8? 

16 

il 

H 3 

7 t 

30 OO 

45 00 

Adam 

81 

61 x 81 

ill 

21I 

ii 

iof 

38 OO 

54 00 

Agate 

IO 

8x10 

* 3 * 

24I 

if 

I 2 A 

5 ° 00 

67 50 

A lem a 

12 

10 x 12 

16 

33 

2I 

J 5 

64 OO 


Amasa 

15 

12 X15 

19! 

38 

2f 

18 

82 OO 


Arab 

l8 

16 x 18 

2 3X6 

47 

3 

22 

105 OO 


Arbah 

22 

20 X 22 

30 

64 

4I 

28 

145 OO 



When ordering lens fitted with Iris Diaphragm Shutter, by telegraph, 
specify Diaphragm in addition to the code word for size of lens. 


Branches : New York City and Chicago. 
























UNIVERSAL WIDE-ANGLE LENS. 


SPEED f-16 



Figure shows the 6^x8^ Universal Wide-Angle Lens, actual size. 


Description. These lenses represent the best of the symmetrical wide-angle 
lenses, the front and back systems each composed of two elementary lenses. 
They are extremely compact and portable. The substitution of the iris for 
the rotary diaphragm in this lens not only adds to the compactness of the 
mount, but gives a much greater variety of openings. 

Optical The speed is f-16. 

Properties. The image circle embraces an angle of over ioo degrees, of 

which 80 degrees are utilized on the plate for which the various sizes are 
rated. With smaller stops the full angle is obtained on smaller plates. 

Application. The covering power and definition are excellent, and there is very 
little distortion of the image, even with the highest angles. 

The speed of these lenses is sufficient to permit their use for interior 
flash-light and outdoor instantaneous photography. Their great aperture fits 
them for general wide-angle work, and while the images are not as perfect 
with extreme angles as in the anastigmats, they are most satisfactory lenses 
when anastigmat correction is not essential. 


Bausch & Lome Optical Co., Rochester. N. Y. 


44 












PRICE-LIST 


OF 

U niversal Wide - Angle Lenses. 


All Lenses are Furnished with Iris Diaphragm and 
Morocco Cap. 


Telegraphic 

Code. 

No. 

Size of Plate 
Covered 
with 

Stop f- 16 .* 
Inches. 

Equiva¬ 

lent 

Focus. 

Inches. 

Back 

Focus. 

Inches. 

Diameter 

of 

Lenses. 

Inches. 

Diameter 

of 

Image 

Circle. 

Inches. 

Price. 

Wade 

5 

4X5 

3* 

3* 

1 

81 

$16 00 

Wait 

8 

5x8 

5* 

4-i 

f 

J 3 

20 00 

Walk 

8i 

6|x 8i 

6\ 

6tV 

1 


24 00 

Walrus 

10 

8 x 10 

8 

7* 

i£ 

18 

28 00 

Water 

14 

11 x 14 

ioi 

9 i 

i£ 

2 5^ 

36 00 

Weaver 

!7 

14 X 17 

14 

1 3i 

2 

3 2 

48 00 

Wale 

22 

18 X 22 

1 7 

16 

2? 

37 

60 00 

Whistle 

3° 

25 X 3 0 

22 

2df 

2 | 

49 

90 00 


* The next size plate is well covered when using small stop, giving 95 degrees angle. 


Branches: New York City and Chicago. 

















BAUSCH & LOMB 
TELE-PHOTO ATTACHMENT 



The Figure shows the Tele-Photo Attachment as applied 
to a Photographic Lens. 


Description. The purpose of the Tele-Photo attachment is to produce larger 
picture's in connection with a photographic lens than can be obtained with 
the lens alone. 

The Tele-Photo attachment is so designed that any ordinary photo¬ 
graphic lens may be used with it. It possesses the advantage over a single 
long-focus lens that it does not require nearly as long a camera or extension 
of bellows to obtain the same magnification, and over the fixed tele-photo 
lens that it is easily applicable to lenses already in use, thus greatly reducing 
the cost and permitting a considerable variation in focus. 

The attachment consists of an achromatic negative system mounted in a 
barrel with sliding tube, which is adjustable by rack and pinion. 

The front of the barrel is threaded to receive the photographic lens, 
and the rear end is provided with a flange for attachment to the front board 
of the camera. The sliding-tube has scale indicating the exact amount of 
magnification. 

Optical In the construction of this negative system, the greatest latitude 

Properties. has been allowed for variation in the lenses with which it is to 

be used, but it must always be borne in mind that any lack of sharpness in 
the image formed by the photographic lens will be exaggerated by the Tele- 
Photo attachment in direct proportion to the amount of enlargement, hence 
only lenses of the highest grade are suitable for tele-photo work. 

Our Tele-Photo attachment permits a variation of magnifying power from 
three to eight diameters by simply adjusting the distance between the negative 
and positive lenses with the rack and pinion. 

Application. There are many objects so situated that they cannot be satis- 
Photographing factorily photographed with an ordinary lens, but may be, 

objects. readily, from a distance. In such cases a magnified (tele-photo) 

picture is required. 


Bausch & Lomb Optical Co., Rochester, N. V. 


46 











































PRICE-LIST 


OF 

Bausch & Lomb Tele-Photo Attachment. 


DISTANCE FROM THE FRONT BOARD TO THE GROUND GLASS. 


Size. 

Equiva¬ 

lent 

Focus of 

Magnification. 

Resulting Focus when used with Tele-Photo Attachment. 

Price. 

Photo 

Lens. 

3 

4 

5 

6 

7 

8 

Inches. 

Inches. 

Inches. 

Inches. 

Inches. 

Inches. 

Inches. 

Inches. 


4 X 5 

61 

6f 

9 t 

12! 

l 61 

19! 

22| 

$16 OO 

5x8 

8f 

8| 

1 3 

I 7 l 

22 

261 

3 1 

18 00 

61 x 8! 

1 i| 

iol 

16I 

22l 

28! 

34 * 

40I 

20 00 

8x10 

* 3 * 

* 3 ? 

20! 

27! 

34 * 

41I 

481 

24 OO 

Telegraphic 

Code. 

Size. 

Inches. 

Diameters of Image Circle. 

When used with Tele-Photo Attachment. 


Tab 

4 X 5 

5 * 

7 * 

9 * 

12 

*5 

17 ? 


Tabby 

5x8 

61 

9! 

12I 

i6i 

19! 

22l 


Tabid 

61 x 81 

8 

11 

14! 

18 

22 

26 


Table 

8x10 

9 

!2f 

16I 

2 of 

26 

3 ° 



N. B.—We do not advise the fitting of Tele-Photo Attachment to any 
except the very best quality lenses, as results will not be satisfactory. 

Lenses should in all cases be sent us in order to secure correct adjustment 
and fitting. 

The scale indicating magnification is computed for prevailing foci of 
photographic lenses, but special standardized scale will be made at an extra 
cost of 75 cents. 


Branches : New York City and Chicago. 


47 





























PROJECTION LENSES. 



Figure shows the 1/4 Plate Objective two-thirds actual size. 


Description. These lenses are designed for projecting magnified images of 
positive pictures on the screen, and are used in the stereopticon, magic 
lantern, etc. The lenses are mounted in a nickeled tube, which is adjust¬ 
able by rack and pinion for rapid and accurate focusing. Each lens also 
has a flange for attaching to camera board. The working parts are all 
constructed with great accuracy, and will be found to work much smoother 
than those of other lenses now on the market. 

Optical These lenses are especially designed for projection purposes and 

Properties. utilize an exceptionally large amount of the light of the lantern, 

giving beautifully illuminated, sharp, clear pictures. Their extremely flat 
field gives a clear picture of equal sharpness over the entire screen. Optically, 
these lenses are greatly superior to the imported lenses which have been sold 
for projection work. 

Application. For stereopticon, magic lantern, and all kinds of projection work, 
these lenses should be selected. Where a small picture is to be made to 
cover a large screen at a short distance, the special wide-angle objective 
No. 6 is recommended. 


Bausch & Lomb Optical Co., Rochester, N. Y. 








































PRICE-LIST 


OF 

Projection Lenses. 


All Lenses are Furnished with Leather Cap. 


No. 

Size. 

Tack 

Focus. 

Equivalent 

Focus. 

Diameter 
of Lenses. 

Price. 



Inches. 

Inches. 

Inches. 


I 

4/4 Plate 

10J 

*5 

3 

$3 2 00 

2 

2 / 3 « 

81 

12 

2 ! 

21 00 

3 

1/2 “ 

7 

IO 

2j 

5° 

4 

I /3 “ 

5* 

7i 

i£ 

12 00 

5 

1/4 “ 

\\ 

6 

if 

7 00 

6 * 

1/4 “ 

3 

5 

if 

8 00 


* Wide Angle. 


TABLE SHOWING DISTANCE FROM OBJECT TO SCREEN, DIAMETER IN 
FEET OF PICTURE, AND FOCUS OF LENS WHICH MUST BE 
USED WHEN OBJECT IS THREE INCHES DIAMETER. 



Branches: New York City and Chicago. 


49 
















































PHOTOGRAPHIC PRISMS 



Figure shows the Prism and method of applying' it to the lens. 


Description. These prisms are mounted so as to be entirely protected by the 
metal case. They are attached to the hood of any photographic lens by a 
threaded adapter. The mountings are so arranged as to bring the surface of 
the prism as close as possible to the front of the lens, thus securing the 
greatest effective angle of the lens and the maximum illumination and speed. 
The glass is of the purest quality and greatest possible light transmitting 
properties. 

Optical The three surfaces are optically plane and have the highest 

Properties. possible polish, thus giving the least loss of light. There is no 

interference whatever with the sharpness of the image produced by the lens. 

Application. The prism is used to reverse the image formed by the lens, from 
left to right, thus making it unnecessary to strip and turn the films in process 
work. 

It effects a great saving in time and labor, and obviates the danger of 
stretching or damaging the film during manipulation. 


Bausch & Lomb Optical Co., Rochester, N. Y 


5° 









PRICE-LIST 


OF 

Photographic Prisms. 


Full 

Aperture 

of 

Prism. 

Inches. 

Figures in the margin show correct size Prism for Lenses as below. 

Price. 

Bausch & Lomb 

Zeiss 

Planar. 

Series la. 

Bausch & Lomb 

Zeiss 

Anastigmat. 

Series Ila. 

Bausch & Lomb 

Zeiss 

Anastigmat. 

Series IV. 

Bausch & Lomb 

Zeiss 

Anastigmat. 

Series V. 

Bausch & Lomb 
Zeiss 

Convertible 

Anastigmat. 

Series Vila. 

When 
fitted to 

B & L-Zeiss 
Lens. 

When 
fitted to 
Lenses of 
other make. 

2 ! 

No. 12 

No. 6 

No. 7 

No. 9 

No. 16 

$ 45 00 

O 

O 

2 ! 

No. 13 

.... 

.... 

.... 

.... 

53 00 

55 00 

3 

No. 14 

No. 7 

No. 8 

3 

p 

M 

O 

No. 19 

65 00 

67 00 

3 ^ 

No. 15 

No. 8 

.... 

.... 

No. 22 

00 

O 

0 

80 00 

4 

No. 16 

.... 

.... 

.... 

No. 25 

90 00 

93 00 

4 i 

No. 17 

.... 

No. 9 

.... 

No. 28 

140 00 

O 

O 

ro 

ri* 

M 

5* 

00 

H 

6 

£ 

.... 

No. 10 

.... 

No. 30 

180 00 

185 00 


In estimating the size of prism which is required for a particular lens, a 
size should be selected which is at least equal to the diameter of the hood. 
A size which is larger than this is preferable, but under no circumstances 
should a smaller one be selected, as, in the work in which these prisms are 
required, it is of great importance to utilize all the light which the lens can 
transmit. 


Branches: New York City and Chicago. 



















THE IRIS DIAPHRAGM SHUTTER. 



The construction of the Iris Diaphragm Shutter is based on a careful 
consideration of the optical principles involved, and it is without question the 
most scientifically correct shutter yet produced. 

The following are some of its advantages: 

It is placed between the systems of the lens, at the diaphragm point, thus 
acting as stop and shutter at once. No extra stops or iris diaphragm are 
needed. 

It gives absolutely uniform illumination over the entire plate. 

It gives brilliant high lights, and at the same time definition in the 
shadows. 

It gives automatically any exposure from one one-hundredth of a second 
to three seconds. It gives time exposures of any duration. 

It has setting device to give any size opening from pin-hole to the largest 
stop. 

It is operated either by pneumatic bulb or finger release. 

A simple turn of the setting lever makes it ready for exposure. 

It cannot open, or expose the plate, while being set. 

It does not jar the camera, even when working at the highest speed. 

It can be applied to any lens, and always improves its covering power and 
depth of focus. 

It can be arranged for use with two or more lenses. 

It is especially adapted for hand camera lenses. 

Bausch & Lomb Optical Co., Rochkster, N. Y. 


52 










In devising the Iris Diaphragm Shutter we have succeeded in equalizing 
the distribution of light over the entire plate more perfectly than is possible 
with any other construction. 

It can be easily proven, both theoretically and by actual experience, that 
as the size of stop is decreased, the lens has not only greater covering power, 
but the illumination (exposure) becomes more uniform. Furthermore, it is well 
known that exposures with large openings give greater contrast between the 
high lights and shadows, while with small stops and long exposures, greater 
detail is obtained in the shadows. For this reason a shutter constructed on 
the iris diaphragm principle, opening in the center with a minute aperture, 
and gradually enlarging to the full opening desired, then gradually reducing 
its opening to the closing point, gives the high lights full value and sharpness, 
depth of focus, and detail in the shadows approaching the results obtained 
with small stops, so that in actual use the diaphragm shutter gives greater 
covering power, more equal illumination, and greater depth of focus than is 
possible with any other form of shutter. This principle having been brought 
before the public by the introduction of our shutter, a number of prominent 
optical firms in Europe have recognized its advantages, and have endeavored 
to construct shutters embodying the same principle, but they are prevented 
by our patents from following our construction, and hence cannot obtain the 
advantages which our shutter alone possesses. 

The popularity of the Iris Diaphragm Shutter is greater to-day than ever 
before, both in America and abroad. It is used in every quarter of the globe 
in which photography is practiced, and from the hot, moist atmosphere of the 
Indian jungles to the Peary-traversed wilds of Greenland, has proven its 
adaptability to every climate and every condition. 

While the Iris Diaphragm Shutter meets all requirements for instantaneous 
work, we disclaim its suitability for ultra rapid photography, although surpris¬ 
ing results, such as trains running sixty miles per hour, and trotting horses, 
show its capacity under suitable management. 

For all except the ultra-rapid, it has no competitor. 


Price-List of Iris Diaphragm Shutter. 


SIZE. 

When Fitted to 
Rapid Universal. 
Extra-rapid Universal, 
with Regular Barrel 
and Diaphragm. 

When Fitted to 
Lenses of 

Other Manufacture, 
Leaving Barrel 
Intact. 

Alvin G. Clark. 

Bausch & Lomb- 
Zeiss Anastigmat 
Series II, Ila, 
and III. 

4x5 

$14 OO 

$14 5° 







4 i) . 

11 

L , 

5x8 

15 OO 

15 5° 

5 >■ $*5 00 

^ J 

31 

r $15 00 





4 J 


6£x 8* 

16 OO 

16 50 

8£ 16 00 

i] 

16 00 

8x10 

i7 5° 

18 00 

10 17 50 

7 

17 5° 


Branches: New York City and Chicago. 


53 














Price-List of Iris Diaphragm Shutter . — Continued. 



Bausch & Lomb- 








Zeiss Anastigmat 

Bausch & Lomb- 

Bausch & Lomb- 

Bausch & Lomb- 

SIZE. 

Series II and I la. 

Zeiss Anastigmat 

Zeiss Anastigmat 

Zeiss Anastigmat 


Special for 

Hand Cameras. 


Series Ilia. 


Series IV. 


Series V. 

4x5 

1 ' ] 

2 t > $14 OO 

3+J 

o'' 







OO 


0 > 


3 




I 


3 


4 


5x8 

O 

O 

TO 

M 

Tf lO 

2 

- $15 OO 

t 

" $15 OO 

5 

6 

* $15 5 ° 


3 


6j 


7 




4 




8 




5J 






61 x 81 


6 

7 

16 OO 

7 

16 OO 

9 

16 OO 

8 x 10 


8 

x 7 5 ° 

8 

1 7 5 ° 




SIZE. 


4 x 5 


5 x 8 


8x10 


Bausch & Lomb- 
Zeiss Anastigmat 
Series VII. 


0 

2 

3 

4 


>15 00 


16 


1 7 5 ° 


Bausch & Lomb- 
Zeiss Anastigmat 
Series Vila. 


9 

11 

1 3 


14 

16 

15* 

17* 

iS* 


>15 


[6 00 


I 7 5 ° 


Bausch & Lomb- 
Zeiss Anastigmat 
Series V I la. 
Special for 
Hand Cameras. 


It 
2t 

3 I ^ 

5t 

7 t. 


$14 00 


Telegraphic 

Code. 


Dalphon 


Danites 


Dara 


Darius 


♦Gives effective aperture when lens is used as a doublet, but reduces speed of the single combination of 
longest focus. 

t Owing to additional work involved when so adapted, no extra barrel is supplied. 


To graduate disk to correspond with stops accompanying lens, extra, 50c. 

Finger release attachment to shutters, 5 x 8 to 8 x 10 size, extra, $1.00. (4x5 is regularly 
supplied with finger release at no additional cost.) 

Telegraphic code refers to shutters in brass mounting; if desired in aluminum it should 
be so stated. 

Size of Opening, in inches, 

Size of Shutter f 0ver an a d' W Mu? ht l 


if 


2f X4 


3^x4! 


if 

3f x 5i 


if 

41x5! 


54 


Bausch & Lomb Optical Co., Rochester, N. Y. 
































THE UNICUM SHUTTER. 



Figure shows the 4 x 5 Unicum Shutter actual size. 


The Unicum Shutter is of the same general form as the Iris Diaphragm 
Shutter, and is intended to meet the demand for a cheaper, yet well made 
and durable shutter. 

The case of the Unicum Shutter is of highly finished bronze metal, and 
the actuating mechanism is well protected from dust and injury. 

The shutter blades are of thin rubber, so shaped as to give the most even 
illumination possible with two blades only, the aperture formed by them 
being at first elliptical, becoming circular. 

Back of the shutter blades there is an iris diaphragm, operated by the 
index lever at the lower margin of the shutter, by which any desired size of 
stop can be obtained. 

This shutter gives automatic exposures from one one-hundredth of a 
second to one second, and has, in addition, a “bulb exposure” so arranged 
that compression of the pneumatic bulb opens the shutter, and the blades 
remain open as long as the bulb is compressed, closing instantly when it is 
released. This is a very useful feature, as short exposures over one second 
can be made with sufficient accuracy, and in photographing children, animals, 
and other objects where their movements are uncertain, it is also possible to 
obtain a much longer exposure with the bulb than it would be safe to hazard 
with the automatic exposure. 

The shutter also has regular time exposure, the blades being opened by 
pressure of the bulb, and remaining open until closed by again pressing 
the bulb. 

Branches: New York City and Chicago. 


55 











Accuracy of exposure and freedom from jar are secured by our pneumatic 
retarding device. 

The Unicum Shutter can be fitted between the combinations of all lenses 
except where they are extremely close together. 

The tens of thousands of these shutters, which are now in daily use in 
all parts of the world, vouch for their correctness of construction and superior 
workmanship. 



Price-List of Unicum Shutter 

When fitted to lenses as specified. 


SIZE. 

Size of 
Opening. 

Inches. 

Rapid Universal, 

A. G. Clark, 
and Extra-rapid 
Universal Lenses. 

Bausch & Lomb- 
Zeiss Anastigmat 
Series II, 

Ila, and III. 

Bausch & 
Lomb-Zeiss 
Anastigmat 
Series Ilia. 

Bausch & 
Lomb-Zeiss 
Anastigmat 
Series VII. 

Bausch & 
Lomb-Zeiss 
Anastigmat 
Series Vila. 

4x5 

1 

8 

", , . . . . 




r 

2 

3 

4 

5 

6 

7 

8 


5x8 


3i x 4} l 

4 x 5 f 

•} 

2 1 

h 

i] 

r 








ioj 


6£ x 81 

I f 

5 x8 l 
6ix8ij 


if 

4 


i 



SIZE. 

Price. 

Price when Fitted to Other Lenses. 

With 

Retarding Device. 

Without 

Retarding Device. 

With 

Retarding Device. 

Without 

Retarding Device. 

4 x 5 

$ 8 oo 

$6 50 

$ 9 OO 

$7 5 ° 

5 x 8 

9 oo 

7 5 ° 

10 00 

8 50 

6|x8i 

IO oo 

8 50 

IO 00 

9 5 ° 


5 6 


Bausch & Lomb Optical Co., Rochester, N. Y. 


































THE BAUSCH & LOMB 
STEREOSCOPIC SHUTTER. 



Figure shows Stereoscopic Shutter two-thirds actual size. 


In designing this shutter we have applied the desirable features of the 
Iris Diaphragm Shutter, the actuating mechanism and pneumatic retarding 
device being the same. The exposure is made by two thin rubber blades 
opening vertically, the openings being diamond shaped. The opening and 
closing of the leaves is absolutely synchronous, thus making both pictures 
exactly alike. 

The centers of the openings are 3 }£ inches apart. The speed regulator 
gives all speeds from one one-hundredth of a second to three seconds. Time 
exposures of any desired duration over three seconds may be made with the 
pneumatic release or finger release, as desired. 

Where extremely rapid exposures are required, the shutter blades will be 
made to open horizontally, with a rectangular opening across the entire 
aperture, becoming slightly wedge-shaped at full opening. This form is 
supplied only on special order. 

The Stereoscopic Shutter is screwed directly to the front board of the 
camera. 

We can assume no responsibility as to satisfactory fitting unless the lenses 
to be used with the shutter are sent here to be fitted. 

Price $ 18.00, fitted to lenses. 


The Stereoscopic Shutter may be fitted to the following sizes of our lenses. 


Extra-rapid 

Rapid 

A. G. Clark. 

Zeiss Anastigmat. 

Universal. 

Universal. 

Series II. 

Series I la. 

Series III. 

Series Ilia. 

No. 00 

No. 5 

No. 5 

No. 2 

Nos. 2 & 3 

Nos. 2 & 3 

Nos. 2 & 3 


Branches: New York City and Chicago. 


57 



















THE BICHROMATE OF POTASH 
RAY FILTER. 



The Ray Filter is, as its name implies, a light filter for the purpose of 
absorbing, from the light which reaches the lens, certain rays the presence 
of which would render the making of a natural picture with true color values, 
clouds, and perspective impossible. 

The Ray Filter prevents over-exposure of the sky, and gives not only the 
correct gradation cf shading from zenith to horizon, but reproduces clouds 
and the detail in the clouds as well. 

The Ray Filter gives the true color value of all objects in the picture. The 
artist, in drawing or painting, depends entirely on color values to individualize 
objects and develop their proper relative position. The photographer, in 

order to overcome the tendency 
to flatness in his monochrome 
picture, must reproduce color 
values with the greatest possible 
accuracy. 


A Rayfi'.tcry-raph. 


The two views of the same scene, one made 
with the Ray Filter and the other an ordinary 
photograph, are introduced to demonstrate 
practically the value of the Bichromate of Pot¬ 
ash Ray Filter in landscape work. 


A Photograph. 


The Ray Filter prevents halation by absorbing the rays which cause the 
halation, hence non-halation plates may be dispensed with when it is 
employed. 

The Ray Filter improves the defining power of the lens by absorbing 
those rays for which the average lens is not well corrected. 

The Ray Filter gives distinct pictures of distant objects, such as mountain 
peaks, which cannot be photographed at all without it, by absorbing the 
highly refractive rays which cause the blurry mist that fills up the distance in 
ordinary photographs of mountainous country. 

In short, the Ray Filter is the equalizer which compensates for the super¬ 
sensitiveness of the photographic plate to ultra-violet, violet, and blue light, 
and its lack of sensitiveness to the red. 

In Europe the Ray Filter has been known and used in a crude form for 
many years, and European as well as American photographers have not been 
slow to take advantage of the improved Bichromate of Potash Ray Filter. 


58 


Bausch & Lomb Optical Co., Rochester, N. Y. 













Our Ray Filter consists of two thin pieces of optical glass, the surfaces of 
which have been ground perfectly plane and parallel, Between these plates 
is cemented a glass ring of uniform thickness throughout, thus forming a cell 
in which the Bichromate of Potash solution is contained. The glass part is 
mounted in a neat metal ring, which protects it. 

The glass cell and mounting forms the basis for the most practical ray 
filter which can be made for the three-color photo-engraving process, as the 
cells may be filled with fluids of any desired color, and the shade can be 
varied easily and indefinitely by diluting or strengthening the solutions. 
Furthermore, the liquid color screen does not degenerate as film screens do. 
We have furnished a considerable number of cells for this purpose, and they 
give excellent satisfaction. 



A Rayfiltergraph. A Photograph. 

Both pictures are of the same bouquet; one made with the Ray Filter, the other without, 
and demonstrate the effectiveness of reproducing color values correctly. 


The Ray Filter fits on the front of the lens exactly as a cap does. It is 
therefore in the most convenient position in case it is desired to remove it for 
any purpose. 

The Ray Filters are made in four forms: style “A,” in which the portion of 
the mounting which fits upon the hood of the lens is lined with cork. This 
form must be fitted to the lens for which it is intended, and it is therefore 
necessary when ordering style “A” to send the exact measure of the circum¬ 
ference of the lens hood. 

Style “ B ” is similar to style “A,” except that, instead of a cork lining for 
holding the filter upon the lens hood, it has three binding screws so that it 
may be fitted to lenses varying in size from the diameter given in table to 
one-half inch smaller. 

The No. “ i P ” Ray Filter is like style “A,” except that it is the proper 
size to fit the 4x5 or 5x8 Folding Kodak, Premo, Poco, Montauk, Sunart, 
and other camera lenses, ’98 model, and is not lined with cork, and it is only 
necessary to specify the lens for which it is intended. 

The No. “ 1 FF” is intended for box cameras with fixed focus lenses, in 
which the lens does not have a mounting projecting beyond the front of the 


Branches: New York City and Chicago. 


59 








camera. The Ray Filter is mounted in a metal ring which slips into an extra 
flange. The flange has three screws by which it is fastened to the front 
of the camera. The Ray Filter may thus be used on the camera, and quickly 
removed when desired. 



Style A. 


Style B. 


Style iP. 


Style i Ft'. 


Price-List of Bichromate of Potash Ray Filters. 

Each filter is packed in a neat box, with a bottle of fluid, and 
pipette for refilling. 


Number. 

Inside Diameter 
in Inches. 

Price. 

Price of 
Morocco Cap. 

iP 

T 3 

I 8 

$ 3 2 5 

$ 7° 

iFF 

if 

3 2 5 

75 

i 

if 

3 2 5 

7° 

2 

if 

3 5° 

7° 

3 

2 t 3 6 

3 5° 

75 

4 

2TS 

4 oo 

8o 

5 

2tt 

4 5° 

9° 

6 

3t 

5 00 

I oo 

7 

3f 

5 5° 

I IO 

8 

4i 

6 oo 

I 20 

9 

4t 

8 oo 

1 35 

IO 

5 * 

IO oo 

1 5° 


When ordering style “A” Ray Filter, send strip of good paper just reach¬ 
ing around the hood of the lens. 


Bausch & Lomb Optical Co., Rochester, N. Y. 
6o 










THE ICONOSCOPE. 



Photographic Enlargement of the Image in the Iconoscope 
Shows Definition to Margin of Field and 
Rectilinear Image. 


Description. The purpose of a finder is to give a reduced image of that 
portion of the view of which a photograph is desired. It should, therefore, 
give an exact reproduction of that 
view in miniature. 

A perfect finder should meet the 
following requirements: 
what a The image should have 

Finder the same proportions as 

should Be. the plate in the camera. 

The angle of view of the finder should 
be the same as that of the lens in the 
camera. 

The image should be so bright as 
to be easily seen under all conditions, 
sharply defined to the extreme edges, 
and free from reflections. Objects 
should appear in their natural position 
— not upside down, or the left where 
the right should be. 

All finders heretofore constructed 
What other have been lacking in several or all of the above respects, giving 

Finders Are. a very dim, poorly defined, reversed or inverted image, reflec¬ 

tions interfering with the distinctness of the image, image projected vertically 
or horizontally so that the operator is forced to assume an unnatural and 
unsteady position in order to watch the image, a fatal defect for hand 
camera work. 

importance Since for the majority of work, and for all hand camera work, 

of a one is absolutely dependent upon what he sees in the finder, the 

Finder. existence of any of these defects should be sufficient to bar it 

out of the list of efficient photographic accessories. 

iconoscope The Iconoscope is an instrument of precision, constructed on 

the correct optical principles, and possesses none of the defects 

ideal Finder, mentioned above, even in the smallest degree. It is, therefore, 

the ideal finder. 

Particular care has been given to the mechanical construction. Accuracy, 
Elegant convenience, stability, and pleasing appearance have been so 

Appearance. combined that the Iconoscope is a decided addition to the 
appearance as well as the effectiveness of any camera. 

Brilliant The image is even more brilliant than the actual objects appear 

image. to the eye, being formed by a concave lens which projects the 

picture through a solid glass prism direct to the eye. One sees with the 
Iconoscope all that is visible to the eye alone. 

Sharply The image is as sharp and clear as that formed by a good 

Defined and photographic lens, and is perfectly rectilinear, so that not only 

Rectilinear. 0 pj ec t s a s a whole may be clearly seen, but every detail, 

position, or expression as well. 

Not Reversed The image is not reversed or inverted, hence objects appear in 
or inverted. their natural position. 

The adjustable hood prevents all reflections and permits the image to be 
viewed without shading the instrument. It is held in the proper position by 
Convenience a spring click. The image is projected at a convenient angle, so 
in Use. that the photographer stands in a natural position and easily 

glances from the image to the object without moving the head. 


Branches: New York City and Chicago. 


6i 











Perfect 

Mounting. 


The mounting of the Iconoscope is extremely ingenious, and, 
being of metal throughout, forms a perfect protection for the 
glass parts without undue weight. 

The mounting proper is attached to a small metal slide piece (“ S ” Fig. 3) 
by a spring hinge, so that, whether the camera is used for vertical or horizontal 
pictures, the Iconoscope is always vertical. 

The slide works in a metal bed-plate which is attached by screws to the 
bed of the camera. 

The Iconoscope may thus be instantly detached if desired, or by 
having several bed-plates may be used on any number of cameras 
with equal facility. 

The Iconoscope is made in three sizes, in each of which the proportions 
of the image are exactly the same, although varying in size. The larger 
sizes, therefore, give larger images, and permit a more precise judgment of a 
view. The smallest Iconoscope is applicable to and may be conveniently 
enclosed in the smallest folding hand cameras to which ordinary finders 
are fitted. 


One 

Iconoscope 
for Several 
Cameras. 



Fig. i. Iconoscope as ordinarily used. 

Fig. 2. Iconoscope in position for vertical view. 

Fig. 3. Diagram showing the use of parts of the Iconoscope- 

H. Hood. The hood may be folded down flat when the 
camera is closed. 

B. Bed-plate attached to the camera bed by screws. 

S. Slide piece attached to the Iconoscope and sliding in the 
groove of B, so that the Iconoscope can be instantly 
removed from the camera if desired. 

V. Vertical attachment consisting of a metal plate with 
oblong opening, and hinged to the base of the Icono¬ 
scope. The vertical attachment when swung up in 
front of the opening O gives vertical pictures (Fig. 2), 
and is folded under the Iconoscope out of the way 
when the full aperture of the instrument is desired 
as for horizontal pictures (Fig. 1). 

C. Spring Click which holds the hood in position. 

Fig. 4. Diagram showing path of a ray of light througn the 
and apparent position of the projected image. 





Iconoscope, and the angle 


PRICE-LIST OF ICONOSCOPES. 

Each Iconoscope is furnished in a neat box. 

Size A . . Height, ii in. . . Width, 1 in. . . Depth, 1 in. . . Each, $5 00 

Size B . . “ ii “ . . “ ij “ . . “ ij “ . . “ 5 50 

Size C . . “ 2 “ . . “ ii “ . . “ ij “ . . “ 6 00 

Extra Bed-plates. “ 75 


62 


Bausch & Lomb Optical Co., Rochester, N. Y. 

























BAUSCH & LOMB-ZEISS STEREO FIELD GLASS. 



The photographer will find a good field glass a very agreeable companion. 
It will save him many a hard climb and time-consuming journey, besides 
adding greatly to the pleasure of every trip. 

Our new Stereo Field Glass is superior to all others in power, field, range, 
stereoscopic effect, compactness, lightness, and elegance of appearance. In¬ 
dispensable when touring, yachting, cycling, racing, at the games, and for 
military observations. Booklet postpaid. 


FOCUSING AND RETOUCHING GLASSES. 



Number, . . . 252 253 254 255 256 257 258 259 260 261 

Diameter, inches, 2 2? 2k 2| 3 3? 3I 3! 4 4! 

Price, each, . . $ .80 .90 1.00 1.25 1.50 1.75 2.00 2.25 2.50 3.25 


REDUCING GLASSES. 



Number, . . . 252CC 254CC 256CC 2580c 260CC 262CC 

Diameter, inches, 2 2 1 3 3I 4 5 

Price, each, . . $1.50 2.00 2.50 3.00 4.00 6.00 


Branches: New York City and Chicago. 


63 





















HASTINGS’ APLANATIC TRIPLET MAGNIFIER. 



No. 35-39. 


As a fine focusing glass and for examining all small objects, minerals, 
chemical crystals, etc., this lens will be found the best, as it is constructed 
after a formula by Professor Charles S. Hastings of Yale University. 


Number. 

Magnifica¬ 

tion. 

Focal Length. 

Real Field. 
Mm. 

Price. 


Inches. 

Mm. 


35 

5 *° 

2 

5 1 -° 

40.0 

$7 00 

36 

6.7 

if 

38.° 

30.0 

7 00 

37 

10.0 

I 

2 5 -° 

20.0 

7 00 

38 

15.0 

' 1 

I9.O 

14.0 

0 

0 

39 

20.0 

1 

2 

I3.O 

7-5 

7 00 


APLANATIC TRIPLET LENS. 



No. 30-32. 

The Aplanatic Triplets, while not having as large field as the Hastings 
lenses, give very good definition, and have good magnifying power. 


Number. 

Magnification. 

Focal Length. 

Price. 



Inches. 

Mm. 


3 ° 

IO 

I 

25.° 

$4 00 

3 1 

14 

* 

18.O 

4 00 

3 2 

20 

1 

2 

12.5 

4 00 


Bausch & Lomb Optical Co., Rochester, N. Y. 

64 






























CONDENSING LENSES. 


The Condensing Lenses listed below are accurately ground and polished, 
and will be found much superior to the imported lenses commonly employed 
for this purpose. When condensers are wanted mounted, we supply them in 
our improved mounts, which are so constructed that there is the least possible 
danger of the lenses breaking when heated. The mountings are also very 
neat and compact. 


Diameter. 

Inches. 

Focus. 

Inches. 

One Lens. 

Unmounted. 

Pair of Lenses. 
Mounted. 

4 

5^ or 6i 

$ I 25 

$ 4 00 

4 -i 

5! or 6| 

1 35 

5 00 

4 * 

52 or 6f 

1 5 ° 

6 00 

5 

6| 

1 75 

7 5 ° 

5! 

8 

2 25 

9 00 

6 

8 

3 00 

12 00 

6 i 

8 

4 00 

18 00 

7 

9 

5 75 

24 00 

8 

12 

7 5 ° 

32 00 

9 

14 

10 00 

40 00 

10 

J S 

1 3 5 ° 

5 ° 00 

12 

18 

27 00 

80 00 

14 

21 

40 00 

120 00 



BRASS 

FLANGES 

FOR 

LENSES. 




Number, . . . . 

. . I 

2 

3 

4 

S 

6 7 8 

9 

10 

11 

Diameter, inches, . 

• • i| 

if 

2 

,1 

Sf 

2 ! 

3 3i 4 

5 

Si 

6 

Price, each, . . . 

. . $ .50 

.50 

•75 

1.00 

1.00 

1.25 1.50 1.75 

2.00 

2.50 

3.00 


MOROCCO 

CAPS 

FOR 

LENSES. 




Number, . . 

. . 1 

2 

3 

4 

5 6 

789 

IO 

II 

12 

Diameter, inches, . 

. . if 

*f 

1! 

2 lS 

2 T6 2 i 

2 f 3i<r 3x6- 

4 t 1 6 

4t®6 

5 A 

Price, each, . . . 

. . $ .60 

.60 

• 6 5 

.70 

•70 -75 

.80 .90 1.00 

1.10 

1.20 

1.25 

GRAINED LEATHER CAPS 

FOR LENSES. 



Number, . . . . 

, . . 1 


l 

3 

4 

5 7 

8 

9 

10 

Diameter, inches, . 

. . if 

I 

1 

2 

2 xV 

1 

2 f 3/x ; 

3X6 

4A 

5i 

Price, each, . . . 

. . . $ .40 

•45 

•5° 

■55 

.60 .70 

.80 

.90 

1.00 


Branches : New York City and Chicago. 


65 



















SIZES OF FLANGES REQUIRED FOR VARIOUS 

LENSES. 


DIAMETER 

OF 

FLANGE. 

Bausch & Lomb-Zeiss Anastigmats. 

Sets of 
Convertible 
Anastigmats. 

Series 

II. 

Series 

I la. 

Series 

III. 

Series 

Ilia. 

Series 

IV. 

Series 

V. 

Series 

VII. 

Series 

Vila. 

1J in. 

If “ 

4 X 5 

4 X 5 
4? x 61 
5x8 

3 t x 4 f 
4x5 
41 x 61 

4 i x 61 
3 ix 4 f 
5x7 

5x8 

6ix8i 

3 tX 4 | 

4 X 5 

5 X 7 

8x10 

10 x 12 

11 x 14 

5 X 7 

61 x 81 

8x10 

10x12 

12x15 

1 

2 

3 

1 

2 

3 

4 

5 

7 


2 “ 

4j x6i 

6i x 8| 

5x7 

. . . 

. . . 


. . . 

6 

8 

10 

C Set 

2 \ “ 

5 x 7 

8x10 

x 81 

7x9 



• • • 

9 

11 

1 3 


2 \ “ 

6|x8i 

10x12 

11 x 14 

8x10 

8x10 

10x12 


. . . 

. . . 

12 

14 

16 

D Set 

3 “ 

8x10 

• • • 


11 x 14 






3 | “ 

10x12 

11 x 14 

. . . 

IOXI2 





1 




Bausch & Lomb Optical Co., Rochester, N. Y- 




































TABLE FOR DETERMINING THE MINIMUM LENGTH OF 

STUDIO. 


Equivalent 


Height of image when subject is 6 feet high. 


Focus 

of Lens. 

3 in. 
High. 

4 in. 
High. 

5 in. 
High. 

6 in. 
High. 

8 in. 
High 

10 in. 
High. 

12 in. 
High. 

16 in. 
High. 

20 in. 
High. 

24 in. 
High. 

30 in. 
High. 

4 inches 

2 / 8/4 

6/4 

5/2 

4/4 








5 “ 

■£■ / IO /5 

3 1 

7/1 1 

6/5 

5/5 

4/2 







6 “ 

6 l I2 / 6 

9/ 6 

7/8 

6/6 

S/P 

4/1 






8 “ 

« \ l6 / 8 

12/8 

10 /3 

8/8 

6/8 

5/6 

4/8 





10 “ 

■| m .y 20/10 


12/10 

10/10 

8/4 

6/10 

5A° 

4/7 




12 “ 

V \ 2 5/° 

19/0 

15/5 

*3/° 

10/0 

8/2 

7/0 

5/6 

4/7 



16 “ 

feet 

U> 

OJ 

4^ 

25/4 

20/6 

17/4 

i3/4 

10/i 1 

9/4 

7/4 

6/2 

5/4 

4/6 

20 “ 

•s f 41/8 

31/8 

25/8 

21/8 

16/8 

13/8 

11/8 

9/2 

7/8 

6/8 

5/8 

24 “ 

1 \ 5°/° 

38/0 

30/10 

26/0 

20/0 

i6 /5 

14/0 

11/0 

9/2 

8/0 

6/10 

30 “ 

S \ 62/6 

47/6 

38/6 

32/6 

25/0 

20/6 

17/6 

*3/9 

11/6 

10/0 

8/6 


TABLE FOR DETERMINING THE DISTANCE BETWEEN 
LENS AND GROUND-GLASS. 


Height of image when subject is 6 feet high. 


Focus 

of Lens. 

3 in. 
High. 

4 in. 
High. 

5 in. 
High. 

6 in. 
High. 

8 in. 
High. 

10 in. 
High. 

12 in. 
High. 

16 in. 
High. 

20 in. 
High. 

24 in. 
High. 

30 in. 
High. 

4 inches 

f 

/ 4 -i 

4.2 

4-3 

4-33 








5 “ 

1 1 

5-2 

■ 5-3 

5-35 

5-4 

5-6 







6 “ 

I 

O 1 

1 6.2 

6.3 

6.4 

6.5 

6.6 

6.8 






8 “ 

1 

8.3 

8.4 

8-5 

8.6 

8.9 

• 9- 1 

9-3 





10 “ 

1 

/ 10.4 

10.5 

10.7 

10.8 

11.1 

11.4 

11.6 

12.2 




12 “ 


\ 12 -5 

12.6 

12.8 

!3 

x 3-3 

13-7 

14 

I4.6 

1 5-3 



16 “ 

1 

i 16.6 

16.9 

17.1 

17-3 

17-8 

18.2 

18.6 

! 9-5 

20.4 

21-3 

22.6 

20 “ 

.2 J 

' 20.8 

21 .X 

21.4 

21.6 

22.2 

22.8 

2 3-3 

24.4 

25-5 

26.6 

28.3 

24 “ 

! 

25 

25-3 

25.6 

26 

26.6 

27-3 

28 

29 -3 

30.6 

32 

34 

30 “ 

5 ' 

\ 3 1 - 2 

31.6 

32.1 

32-5 

33-3 

34-2 

35 

36.6 

38-3 

40 

42-5 


Branches : New York City and Chicago. 


67 















































TABLE FOR COMPUTING THE ANGLE OF VIEW 


Divide the long side of the plate by the equivalent focus of the lens. 


If the 

Quotient is 

The 

Angle is 

If the 

Quotient is 

The 

Angle is 

If the 

Quotient is 

The 

Angle is 

If the 

Quotient is 

I 

The 

Angle is 

.282 

16 Deg. 

.63 1 

35 

Deg. 

1.02 

54 Deg. 

I.48 

73 De g- 

•3 

17 

it 

•G 

3 6 

ii 

1.041 

55 

a 

x -5 

74 “ 

• 3 T 7 

18 

it 

.67 

37 

ii' 

I.063 

56 

a 

x -53 

75 “ 

•335 

T 9 

U 

.689 

38 

ii 

I 086 

57 

a 

I- 5 6 

76 “ 

•353 

20 

a 

.708 

39 

it 

1.108 

58 

u 

x -59 

77 “ 

•37 

21 

a 

.728 

40 

it 

I.13 2 

59 

a 

I.62 

78 “ 

• 3 8 9 

22 

a 

.748 

4 i 

a 

i-' 5 S 

60 

u 

I.649 

79 “ 

.407 

23 

a 

.768 

42 

a 

1.178 

61 

a 

I.678 

80 “ 

•425 

24 

a 

.788 

43 

a 

1.2 

62 

u 

i -7 

81 “ 

•443 

2 5 

a 

.808 

44 

a 

1.225 

6 3 

a 

1 -739 

82 “ 

.462 

26 

a 

.828 

45 

a 

1.25 

64 

a 

1.769 

83 “ 

00 

27 

a 

.849 

46 

a 

1.274 

65 

a 

1.8 

84 “ 

•5 

28 

a 

.87 

47 

a 

i -3 

66 

a 

co 

Oj 

85 “ 

• 5 X 7 

2 9 

u 

.89 

48 

a 

i- 3 2 

67 

u 

1.865 

86 “ 

• 53 6 

3 ° 

u 

.911 

49 

a 

J -35 

68 

a 

1.898 

87 “ 

•555 

3 1 

a 

•933 

5 ° 

a 

x -375 

69 

a 

I - 93 I 

88 “ 

•573 

32 

a 

' -954 

5 i 

a 

1.4 

70 

a 

C965 

89 “ 

• 59 2 

33 

a 

•975 

52 

u 

1.427 

7 i 

a 

2. 

90 “ 

.611 

34 

a 

I. 

53 

a 

1.45 

72 

a 




68 


Bausch & Lomb Optical Co., Rochester, N. Y. 






















What kind of a lens do I want? 


Will it meet my requirements ? 

Are the questions which face the purchaser of a photographic outfit, questions 
which require experience and a thorough knowledge of the optics of lenses, as 
well as of the purpose for which they are to be used, to answer. To aid in 
making a wise selection, we give below the results of our experience in 
supplying the wants of all kinds of photographers. The results which may 
be obtained with a photographic lens (objective) depend upon the care and 
skill with which it is made fully as much as upon its construction. The 
following statements therefore apply only to lenses in which the workmanship 
is the best. 

The leading characteristics to be considered are the following: 

1. Definition. 

2. Rapidity. 

j. Covering Rower. 

4. Freedom from Astigmatism. 

g. Rectilinearity. 

6. Angle of View. 

y. Depth of Focus. 

1. Definition is that quality of a lens which enables it to produce sharp 
and crisp images. If a lens fails in this respect it is of inferior quality. 
Partial correction for this fault may be made by decreasing the opening 
(using smaller stop), but this shuts out light and consequently requires a 
longer exposure. 

In a perfect lens the definition should be faultless with the largest stop. 

2. Speed should be the greatest possible, and at least sufficient for making 
instantaneous outdoor and gallery photographs with unfavorable light. Speed 
depends upon the relation of aperture to focus; that is, the relation of the 
opening (not diameter of lenses) to the focus, and is expressed by a fraction 
of the diameter of aperture, obtained by dividing the diameter of diaphragm 
by the focal length. For example, suppose the diameter of diaphragm to be 
1 inch, and the equivalent focal length of the lens to be 8 inches, the speed 
would be designated by the fraction f-8. 

To meet all conditions for hand camera and outdoor work , a lens should have 
a speed of not less than f—Q. 

Branches : New York City and Chicago. 

69 


j. Covering Power. A lens is said to have perfect “covering power” 
when the image is sharply defined to the margins of the plate. A lens may 
have definition and speed and still be unable to “ cover the plate ” or give a 
sharp image over the full size of the plate used. In general, it may be said 
that the sharper the definition over all parts of the plate, the better is the 
quality of the lens. Again, the better the quality of the lens, the shorter 
the focus which may be used with any given size of plate, thus increasing the 
angle and depth of focus, as well as adding to the compactness of the lens 
itself. 

A good lens should give good definition to the margin of the plate , with large 
opening. 

q. Freedom from Astigmatism. This important improvement, first accom¬ 
plished in the Zeiss Anastigmat lenses, has, to a considerable extent, revolu¬ 
tionized the construction of photographic lenses. Astigmatism is a fault 
inherent in all lenses and lens systems, except those especially constructed 
to eliminate it, and may be defined as the inability of such a lens to 
bring vertical and horizontal lines to a focus at the same time, even though 
such lines lie in the same plane. The elimination of astigmatism from 
photographic lenses remained impossible until the inventor of the Zeiss 
Anastigmat lenses worked out the formula for a glass having the proper 
dispersive and refractive power to correct the ever present astigmatism. 
This glass is now known as Schott-Jena glass, and is used in all our Zeiss 
Anastigmat lenses. 

Anastigmat lenses give correct delineation, hence have better definition and 
covering power; and, on account of better corrections , permit the use of shorter 
focus , giving greater angle , more equal illumination , and greater depth of focus. 

5. Rectilinearity. Rectilinear lenses reproduce straight lines as straight 
lines. Single lenses reproduce straight lines near the margins of the 
plate as curves. The lack of rectilinearity shows most at the margin of the 
image circle, and is most pronounced in short-focus lenses. A lens may have 
speed, definition, covering power, and freedom from astigmatism, and still 
not be rectilinear. 

6. Angle of View. Upon this depends the amount of view included 
within the size of plate. The actual angle is expressed by the extreme rays 
which pass through the diaphragm and reach the margin of the plate. The 
angle, therefore, becomes wider with the decrease in focus on the same size 
plate. The angle for ordinary views is calculated at about 60 degrees. 
When ranging at between 80 and 100 degrees it is called “wide angle.” In 
a wide-angle lens the focus is relatively short and involves the use of smaller 
stops to give covering power, thus reducing speed. Under ordinary condi¬ 
tions the angle of a lens is invariable, so that while it may be rated to give a 
wider angle, this can only be gained by using it on a larger plate. If a wider 
angle on the same size plate is desired, a shorter focus lens must be used. 

A lens should have an angle considerably exceeding that actually required 
for the plate on which it is to be used. 


70 


Bausch & Lomb Optical Co., Rochester, N. Y. 


/. Depth . Upon this quality depends the capacity of the lens to give 
a sharp picture of objects situated at different distances from the camera. 
It may be obtained by the use of small stops, but at the sacrifice of speed. 
With any given stop it is an invariable quality in different lenses of the same 
equivalent focus, whatever may be their construction. It increases with the 
decrease in focus. There is no such thing as a universal focus, except with 
small stops, although short-focus lenses on small plates give a result nearly 
approximating it. 

Lenses of the best quality {Anas tigmat') may be used of shorter focus and give 
correspondingly greater depth, besides greater angle. 

Resume. Assuming the same equivalent focus and rapidity, a double 
combination is superior to a single combination because it has : 

Better definition 
Greater speed 
Greater covering power 
Rectilinearity. 

Assuming the same amount of speed, the Zeiss Anastigmat is superior to 
the Rectilinear lens because it has: 

Freedom from astigmatism 
Greater covering power 
Shorter focus 
Greater depth 
Greater angle 
Greater compactness. 



Branches: New York City and Chicago. 


71 




CHOICE OF LENSES FOR HAND CAMERAS. 


In the subjoined tables we give a resume' of lenses suitable for hand 
cameras, from which a selection can be readily made. For additional infor¬ 
mation on the optical properties of lenses, reference may be made to the 
descriptions. 

Hand cameras require the mountings of lenses to be as compact as it is 
possible to make them in order to allow the camera to fold in a small space. 
We mount our lenses to meet this condition. Since hand camera work 
consists chiefly of instantaneous exposures, it is desirable to obtain speed, 
covering capacity and depth of focus with proper angular field, and the lenses 
recommended in the table combine these characteristics to the greatest pos¬ 
sible extent. The equivalent focus of each is shorter than the diagonal of 
the plate, and longer than its short side. 

In all of these lenses the angle is sufficiently large so that they can be 
used on the next larger plate, thus giving a greater angular range, which is 
an immense advantage. 

It is often desirable, and, in cases of interiors and confined situations, 
absolutely necessary, to use lenses having considerable angle, which can be 
obtained only by using a shorter focus, but in which, at the same time, 
covering power should be retained to the utmost possible extent. We there¬ 
fore give also a table of such lenses (Table II), which can be used under 
favorable conditions for instantaneous exposures. 

An ideal outfit should comprise these two classes of lenses, which are 
made interchangeable in the shutter or barrel, and are optically of the 
greatest possible efficiency. 


TABLE I —MEDIUM ANGLE LENSES. 


SERIES. 

3 \x 4 \ 

4 x 5 

5 x 7 

5 x 8 

6| x 8| 

Ia. 

II . 

Ila. 

III . 

Ilia. 

Ex. Rapid Univ. 
Rapid Universal 
A. G. Clark . . . 

No. 10 

No. 2 

■ No. 1 

No. 00 

No. 0 

No. 4 i 
No. 4 t 

No. 11 

No. 3 

No. 1 

No. 2 

No. 1 

No. 00 

No. 5 

No. 5 

No. 13 
j No. 5 
(No. 6 
No. 3 
( No. 4 
(No. s 
j No. 3 

1 No. 4 
No. 1 

No. 8 

No. 8 

No. 14 

No. 7 

No. 4 

No. 6 

No. s 

No. 2 

No. 8i 
No. 8| 


TABLE II—WIDE ANGLE 

LENSES. 


IV. 

No. 1 

No. 2 

No. 4 


V. 


No. 1 

No. 2 

No. 3 

Universal W.A. . 


No. 5 

No. 8 

3 

p 

Oo 


Bausch & Lomb Optical Co., Rochester, N. Y. 
72 



































Y OF CONGRESS 



0 027 133 090*A 





























